With special permission of the Dark Mod, here's a list of past challenges since the beginning of GS100, updated to the last one ("backfired spell"). Take, enjoy, and if I've missed anything please let me know!
2nd person pov
4 elements (water, fire, air, earth)
http://grangersnape100.livejournal.com/1660757.html 50 points
Addiction
A Deal with Lucius Malfoy
http://community.livejournal.com/grangersnape100/1457515.htmlAdopt a wizard
Advent calendar
http://grangersnape100.livejournal.com/1675397.html#Afterlife
http://grangersnape100.livejournal.com/1466434.htmlAfternoon Tea
http://grangersnape100.livejournal.com/1615113.htmlAge challenge 24 05 09
http://community.livejournal.com/grangersnape100/1205232.htmlAllergy 14 06 09
http://community.livejournal.com/grangersnape100/1213331.htmlAltering appearances challenge
Amnesia
http://grangersnape100.livejournal.com/1627655.htmlAngel of Death
http://grangersnape100.livejournal.com/1493530.htmlAngels and Demons
http://community.livejournal.com/grangersnape100/1409398.htmlAnimagus
http://grangersnape100.livejournal.com/1662097.htmlAnonymous valentine challenge
Any means necessary
http://community.livejournal.com/grangersnape100/1267816.htmlAnticipation
Apologies challenge
Apparition
http://grangersnape100.livejournal.com/1632169.htmlAstronomy tower challenge
At the Veil
http://community.livejournal.com/grangersnape100/1405379.htmlAzkaban challenge (both humour and dark)
Babylon5
Babysitting
Backfired spell
http://community.livejournal.com/grangersnape100/1412884.htmlBack from the dead
Badger
http://grangersnape100.livejournal.com/1517128.htmlBad pickup line
Bathroom gossip challenge
Behind closed doors
Behind the mask
Best of all the lost arts
Betrayal
http://community.livejournal.com/grangersnape100/1452161.htmlBlame it on Crookshanks
http://grangersnape100.livejournal.com/1633934.htmlBlame it on Ron
Blanket
http://community.livejournal.com/grangersnape100/1362644.htmlBlood {C}{C}
http://grangersnape100.livejournal.com/1669354.htmlBlue lips
http://grangersnape100.livejournal.com/1567281.htmlBodyguard challenge 18 01 09
Boggart
Book dedication {C}{C}
http://grangersnape100.livejournal.com/1670552.htmlBookmark
Bookshelf
http://grangersnape100.livejournal.com/1598058.htmlBows and ribbons {C}
http://grangersnape100.livejournal.com/1674189.html#Broken
Broken heart
Broken memory charm
Bruised peaches
http://grangersnape100.livejournal.com/1557928.htmlButtons
By the Sea
http://grangersnape100.livejournal.com/1620379.htmlCaught by Filch
Caught!
Champagne
http://grangersnape100.livejournal.com/1537060.htmlCheese
http://community.livejournal.com/grangersnape100/1216952.htmlChild
Chocolate Body Paint
http://grangersnape100.livejournal.com/1547524.htmlChocolate covered cherries
http://community.livejournal.com/grangersnape100/1320835.htmlChoices
Christmas eve/day
Christmas Memories
http://grangersnape100.livejournal.com/1604879.htmlChristmas tree challenge
Cliché challenge
http://community.livejournal.com/grangersnape100/1334532.htmlCloset house slob
http://community.livejournal.com/grangersnape100/1326420.htmlColdest winter
Collared
http://grangersnape100.livejournal.com/1663630.htmlComfort and joy challenge
Common cold
Compromise
Compulsion
Condemned
Confessions
Corridor of power
http://grangersnape100.livejournal.com/1589409.htmlCountry life challenge
Creative curses challenge or, creative cursing challenge (description: “Merlin’s what?” - creative cursing in the wizarding world)
Crookshanks
Crystal clear
http://grangersnape100.livejournal.com/1672597.htmlCuriosity doesn’t always win out
Cyrano (or playing Cyrano)
http://community.livejournal.com/grangersnape100/1319153.htmlDaddy Long Legs
http://community.livejournal.com/grangersnape100/1383597.htmlDangerous Game
http://community.livejournal.com/grangersnape100/1411797.htmlDark!Hermione
Darkness goes deeper than light
Dating lessons 12 04 09
http://community.livejournal.com/grangersnape100/1186046.htmlDead/death
http://grangersnape100.livejournal.com/1524463.htmlDeadline
http://grangersnape100.livejournal.com/1574949.htmlDeal with Lucius Malfoy
http://grangersnape100.livejournal.com/1625447.htmlDE fluff
Deception
Decorating
Dementors
http://grangersnape100.livejournal.com/1590339.htmlDental exam
Department of Mysteries challenge 25 01 09
Devil’s Advocate
http://community.livejournal.com/grangersnape100/1272404.htmlDialogue only
Dickens’ Christmas Carol
Dinner conversation
Dirty limerick and poetry challenge
Dirty little secret
Divination
http://community.livejournal.com/grangersnape100/1351124.htmlDon’t play with your food
http://grangersnape100.livejournal.com/1544677.htmlDouble standards
Drinking games
http://community.livejournal.com/grangersnape100/1361553.htmlDystopia
http://community.livejournal.com/grangersnape100/1372997.htmlEggnog
Elf made wine challenge
End of financial year
http://community.livejournal.com/grangersnape100/1214232.htmlEnd, the
http://community.livejournal.com/grangersnape100/1410653.htmlEpistolary 08 06 09
http://community.livejournal.com/grangersnape100/1210361.htmlEpitaph
Expecting
Exposed
Family visit
Fancy meeting you here
Fantasies
http://community.livejournal.com/grangersnape100/1311284.htmlFeather boa (fluorescent orange)
http://grangersnape100.livejournal.com/1655858.htmlFelix Felicis
Fever
http://community.livejournal.com/grangersnape100/1226247.htmlFight
Fireside
http://grangersnape100.livejournal.com/1606246.htmlFireworks
http://grangersnape100.livejournal.com/1490793.htmlFirst kiss
First time together
http://community.livejournal.com/grangersnape100/1328637.htmlFirst word
http://community.livejournal.com/grangersnape100/1356150.htmlFlies/vinegar
Floo challenge
http://community.livejournal.com/grangersnape100/1277832.htmlFlowers (flower symbolism)
http://grangersnape100.livejournal.com/1611530.htmlFluffy challenge (can be taken as fluff, or as Fluffy the three-headed dog)
Follow me
http://grangersnape100.livejournal.com/1626349.htmlFoot fetish
http://grangersnape100.livejournal.com/1569671.htmlFornicate or Die
http://grangersnape100.livejournal.com/1519118.htmlFour leaf clover
http://community.livejournal.com/grangersnape100/1251926.htmlFree for all challenge
http://grangersnape100.livejournal.com/1572637.htmlFruitcake
http://community.livejournal.com/grangersnape100/1298854.htmlGift of the magi
Glasses
http://community.livejournal.com/grangersnape100/1353208.htmlGood intentions
http://community.livejournal.com/grangersnape100/1432319.htmlGratitude {C}
http://grangersnape100.livejournal.com/1672999.html#Graveyard visit
Green vs Red
http://grangersnape100.livejournal.com/1602604.htmlGrey night shirt challenge (fluff, dark, pwp)
Grocery shopping
Guilty pleasures (fluff or dark, try to insert the words “guilty pleasure”) 01 02 09
Hagrid’s loose lips 11 01 09
Halloween feast
Handwriting
http://grangersnape100.livejournal.com/1607498.htmlHappy holidays
http://grangersnape100.livejournal.com/1599637.htmlHard to say I'm sorry/forgiveness challenge
http://community.livejournal.com/grangersnape100/1444049.htmlHaunted house
Headache
http://community.livejournal.com/grangersnape100/1305669.htmlHeart lies with the order
Heat wave
Hermione’s bad day
Hermione Spinner’s End challenge
Hermione the Headmistress
Hidden agenda
Hidden evil
http://grangersnape100.livejournal.com/1592811.htmlHidden talent
http://community.livejournal.com/grangersnape100/1388660.htmlHide and Seek
Hogwarts a History
Homesick
Hormones 29 03 09
http://community.livejournal.com/grangersnape100/1176893.htmlHRH (Her/His Royal Highness)
http://grangersnape100.livejournal.com/1624151.htmlHumble pie
http://community.livejournal.com/grangersnape100/1238488.htmlIce Cream
http://grangersnape100.livejournal.com/1645470.htmlI dare you
http://grangersnape100.livejournal.com/1585072.htmlI have a few questions to ask
http://community.livejournal.com/grangersnape100/1449107.htmlI told you so
Imperio Curse
http://community.livejournal.com/grangersnape100/1414160.htmlInanimate object
http://grangersnape100.livejournal.com/1469384.htmlIndecent proposal
http://grangersnape100.livejournal.com/1526439.htmlIndecent proposal
http://grangersnape100.livejournal.com/1559366.htmlInferi
http://grangersnape100.livejournal.com/1521428.htmlIn-laws challenge
http://community.livejournal.com/grangersnape100/1344111.htmlInterrogation
http://grangersnape100.livejournal.com/1580961.htmlIn the dark
In the rain
http://grangersnape100.livejournal.com/1573846.htmlIn Vino Veritas
http://grangersnape100.livejournal.com/1510452.htmlIt’s a wonderful life
http://community.livejournal.com/grangersnape100/1294619.htmlIt’s just an illusion
It was a mistake
Just a dream
http://community.livejournal.com/grangersnape100/1341102.htmlKeep calm and carry on
http://grangersnape100.livejournal.com/1652746.htmlKitten
http://grangersnape100.livejournal.com/1529195.htmlKnock late at night
http://grangersnape100.livejournal.com/1524815.htmlKnockturn Alley
Last One
Late Night Visitor
http://grangersnape100.livejournal.com/1546459.htmlLate Paper
http://grangersnape100.livejournal.com/1504251.html#commentsLeaky Cauldron challenge
Leap year (from the tradition of women proposing to men)
Leather
http://grangersnape100.livejournal.com/1564013.htmlLeaving
Lecture/presentation
Legilimency
http://grangersnape100.livejournal.com/1461550.htmlLemons
http://grangersnape100.livejournal.com/1633515.htmlLife debt challenge (The debt is not limited to SS or HG, SS and HG only need to be in the drabble.) 08 03 09
http://community.livejournal.com/grangersnape100/1158442.htmlLily brigade
http://grangersnape100.livejournal.com/1540947.htmlLily challenge ( 22 02 09)
Little black dress 17 05 09
http://community.livejournal.com/grangersnape100/1201547.htmlLocked in the Dungeon(s)
Lock the door
http://grangersnape100.livejournal.com/1595692.htmlLost and Found
http://community.livejournal.com/grangersnape100/1385977.htmlLost in the Department of Mysteries
http://community.livejournal.com/grangersnape100/1453917.htmlLucius wants Hermione
Lupin saw it all
Madam Puddifoot
http://grangersnape100.livejournal.com/1554646.htmlMagical chastity belt
http://grangersnape100.livejournal.com/1594059.htmlMagical loveseat
http://community.livejournal.com/grangersnape100/1274831.htmlMail or owl order
http://community.livejournal.com/grangersnape100/1455878.htmlMalfoy the suitor challenge 05 04 09
http://community.livejournal.com/grangersnape100/1180859.htmlMarks
http://grangersnape100.livejournal.com/1541733.htmlMarried to another
Marysue
Masquerade (covers “masquerade” and “masked ball”)
Masterchef
http://community.livejournal.com/grangersnape100/1378478.htmlMaternal 10 05 09
http://community.livejournal.com/grangersnape100/1198965.htmlMedal
Mending a broken heart
Mind your own business
Minerva wants a word
Mirrors
http://grangersnape100.livejournal.com/1477258.htmlMistletoe challenge
Moaning Myrtle
Model/modelling (someone is modelling, or an object is used as a model)
http://community.livejournal.com/grangersnape100/1235088.htmlMonster under the bed
Moustache {C}{C}
http://grangersnape100.livejournal.com/1672105.htmlMovie quote
Moving
Muggle devices
Muggle heritage
http://grangersnape100.livejournal.com/1470760.htmlMuggle horror movie
http://grangersnape100.livejournal.com/1666155.htmlMuggle studies
http://grangersnape100.livejournal.com/1634320.htmlMurphy’s Law Challenge
Native slang
Natural hate
Naughty nurse
http://grangersnape100.livejournal.com/1543803.htmlNaughty or nice
http://grangersnape100.livejournal.com/1601568.htmlNever Again
http://grangersnape100.livejournal.com/1614293.htmlNew Year
http://community.livejournal.com/grangersnape100/1302408.htmlNicknames 25 05 08
Nightmare challenge
http://grangersnape100.livejournal.com/1473536.htmlNine levels of hell
http://community.livejournal.com/grangersnape100/1262179.htmlNo dialogue
Not a gentleman
No time
http://community.livejournal.com/grangersnape100/1337962.htmlNot what it looks like
http://community.livejournal.com/grangersnape100/1254285.htmlNursery rhyme
http://community.livejournal.com/grangersnape100/1221401.htmlOffice politics
http://community.livejournal.com/grangersnape100/1229103.html“OH&S” challenge. This challenge involves and occupational health & safety or OSHA type organization. The OH&S can inspect a potions lab, or DADA lab, or issue regulations, etc. This challenge is very open ended and can go fluffy or dark.
http://community.livejournal.com/grangersnape100/1336990.html Oktoberfest
One last
One of these things is not like the other (one not like the other) 15 02 09
Our mrs Snape
Outhouse challenge 26 04 09
http://community.livejournal.com/grangersnape100/1192253.htmlOut of comfort zone
Owl Post
http://community.livejournal.com/grangersnape100/1394715.htmlPage 197
Page 394
http://grangersnape100.livejournal.com/1650115.htmlPain in the arse
PEEVES!
http://grangersnape100.livejournal.com/1520021.htmlPhotograph
http://community.livejournal.com/grangersnape100/1365885.htmlPick Me Please
http://community.livejournal.com/grangersnape100/1379868.htmlPirate
http://community.livejournal.com/grangersnape100/1309013.htmlPlacebo
http://grangersnape100.livejournal.com/1553810.htmlPolishing broomstick/wand
Polyjuice pimp
Portkey
http://grangersnape100.livejournal.com/1560006.htmlPortrait
Possessive!Snape challenge 01 06 08
Potions
Prank
Prefect’s bathroom challenge
“Prince Charming/Prince Un-charming” challenge. This challenge is really open to interpretation. Snape is a “Prince” but the prince can be metaphorical or literal. I am going to extend this challenge to apply to Princess. This challenge is very open ended and can go fluffy or dark.
http://community.livejournal.com/grangersnape100/1344799.htmlProblem child
http://grangersnape100.livejournal.com/1632723.htmlProcrastination
http://community.livejournal.com/grangersnape100/1392384.htmlPrOn challenge
http://grangersnape100.livejournal.com/1572637.htmlProve it!
Public embarrassment
Pumpkin
Random acts of kindness 22 03 09
http://community.livejournal.com/grangersnape100/1172700.htmlRansom captive
http://grangersnape100.livejournal.com/1596236.htmlRed carpet
http://community.livejournal.com/grangersnape100/1219602.htmlRed nose
http://grangersnape100.livejournal.com/1530911.htmlRegency
Research
http://grangersnape100.livejournal.com/1514527.htmlResolutions (New Year)
http://grangersnape100.livejournal.com/1536108.htmlRestrictions
http://grangersnape100.livejournal.com/1571725.htmlRetirement
http://community.livejournal.com/grangersnape100/1358672.htmlReunited
http://grangersnape100.livejournal.com/1583699.htmlRevenge
http://community.livejournal.com/grangersnape100/1398089.htmlRites of Spring
http://grangersnape100.livejournal.com/1549585.htmlRobes on fire
http://grangersnape100.livejournal.com/1637447.htmlRoses
http://grangersnape100.livejournal.com/1579071.htmlRose Snape and Scorpius Malfoy challenge
Rubber duck
http://grangersnape100.livejournal.com/1664806.htmlRunaway
Runes
http://community.livejournal.com/grangersnape100/1333019.htmlSanta Severus
Scream
Secret lovers
http://community.livejournal.com/grangersnape100/1442040.htmlSecret room
http://grangersnape100.livejournal.com/1667735.htmlSecrets
http://grangersnape100.livejournal.com/1552843.htmlSecret Santa
http://grangersnape100.livejournal.com/1532896.htmlSecret wish
Seedy secondary character
Seven deadly sins (the sin serial)
Severus goes shopping
Sex education
Shakespeare Quote challenge (include at least one of these: "Something wicked this way comes"
"O for a Muse of fire"
"Men of few words are the best men"
"I'll not budge an inch"
"Love looks not with the eyes, but with the mind"
"He does it with a better grace, but I do it more natural"
"The gentleman is not in your books"
"It is the green-eyed monster which doth mock"
"This is the very ecstasy of love"
"The lady doth protest too much, methinks")
She waits
Shoes 15 03 09
http://community.livejournal.com/grangersnape100/1166895.htmlSick in bed
Sin serial (tag: the sin serial - much the same take as seven deadly sins)
Size matters
Slave for a week
Sleeping beauty
http://grangersnape100.livejournal.com/1647556.htmlSleeping kneazle
Sleeping on the couch
Sleepover and Unwanted Guest (double challenge, can be used together or separately)
http://grangersnape100.livejournal.com/1463767.htmlSlip of the tongue
http://community.livejournal.com/grangersnape100/1339573.htmlSlughorn’s Christmas party
Slytherin firsties
http://grangersnape100.livejournal.com/1551954.htmlSmut challenge
Snape bath challenge
Snape has it all
Snape saves the day
Snape’s birthday
Snape’s Green Quidditch Robes
http://grangersnape100.livejournal.com/1487959.htmlSnape’s horcrux
http://grangersnape100.livejournal.com/1556150.htmlSnape Watch
http://grangersnape100.livejournal.com/1512071.htmlSnoring
http://grangersnape100.livejournal.com/1507373.htmlSnow challenge
Socks
http://grangersnape100.livejournal.com/1577741.htmlSolstice challenge, or what happens during the longest night of the year in the UK?
Someone else
http://grangersnape100.livejournal.com/1609005.htmlSomeday my Prince will come
http://grangersnape100.livejournal.com/1664397.htmlSomething you had to hear
Somewhere between
Songfic
Spam
http://grangersnape100.livejournal.com/1562108.htmlSpeechless
http://grangersnape100.livejournal.com/1576061.htmlSpelling mistake
http://community.livejournal.com/grangersnape100/1283367.htmlSPEW challenge
Sports and athletics challenge
Spousal duty
Spy007
http://community.livejournal.com/grangersnape100/1247970.htmlStain
http://community.livejournal.com/grangersnape100/1231199.htmlStalker
http://grangersnape100.livejournal.com/1667221.htmlStanding in the shadows
http://grangersnape100.livejournal.com/1662665.htmlStars
http://community.livejournal.com/grangersnape100/1368980.htmlStocking stuffer
http://grangersnape100.livejournal.com/1535405.htmlStorage cupboard
http://community.livejournal.com/grangersnape100/1288494.htmlStuck on you (something stuck on you 01 03 09)
http://community.livejournal.com/grangersnape100/1155530.htmlSubmissive Snape
http://community.livejournal.com/grangersnape100/1322063.htmlTake your kids to work
http://grangersnape100.livejournal.com/1501079.htmlTangled in the tinsel {C}
http://grangersnape100.livejournal.com/1674961.html#Tasteless humour
http://community.livejournal.com/grangersnape100/1447239.html?mode=replyTaste of ss/hg
Tattoo
http://grangersnape100.livejournal.com/1556813.htmlTeach me
Ten years ago
That tickles 03 05 09
http://community.livejournal.com/grangersnape100/1195794.htmlTheft
http://community.livejournal.com/grangersnape100/1375535.htmlThe moment he/she knew
http://grangersnape100.livejournal.com/1570755.htmlThe Senses
Things we cannot do
Things you hide from me
http://grangersnape100.livejournal.com/1659765.htmlThis is madness
http://grangersnape100.livejournal.com/1622545.htmlTime challenge
http://community.livejournal.com/grangersnape100/1458598.htmlTime in a Bottle
http://grangersnape100.livejournal.com/1616827.htmlTime-Turner challenge
http://community.livejournal.com/grangersnape100/1317640.htmlToo close for comfort
http://grangersnape100.livejournal.com/1657016.htmlToys
http://community.livejournal.com/grangersnape100/1292779.htmlTraitor to the light
Transfiguration
http://community.livejournal.com/grangersnape100/1331208.htmlTrapped
http://grangersnape100.livejournal.com/1566017.htmlTrick or treat
Tri-wizard contest
http://grangersnape100.livejournal.com/1481118.htmlTrouble with Harry
Trunk
http://grangersnape100.livejournal.com/1635209.htmlTrust and Obey
http://community.livejournal.com/grangersnape100/1223121.htmlTruth or dare 19 04 09
http://community.livej ournal.com/grangersnape100/1190178.html
Tucking in
Turkey challenge
http://community.livejournal.com/grangersnape100/1285928.htmlTwelve days of Christmas
Twin or doppelganger
http://grangersnape100.livejournal.com/1527736.htmlUltimate challenge
Undergarments
Under the covers
http://community.livejournal.com/grangersnape100/1307375.htmlUnder the Christmas Tree
http://grangersnape100.livejournal.com/1604569.htmlUndone
http://community.livejournal.com/grangersnape100/1242813.htmlUnforgivable curses
Unusual request
http://grangersnape100.livejournal.com/1567139.htmlUsed
http://community.livejournal.com/grangersnape100/1207386.htmlVampire
http://grangersnape100.livejournal.com/1521778.htmlVeritaserum perils
Veterans
http://grangersnape100.livejournal.com/1472305.htmlVoyeur
http://grangersnape100.livejournal.com/1538477.htmlWalks among muggles
War
Warring Familiars
http://grangersnape100.livejournal.com/1499609.htmlWeasley Wizarding Wheezes
http://community.livejournal.com/grangersnape100/1334460.htmlWedding night
http://community.livejournal.com/grangersnape100/1346275.htmlWerewolf
http://grangersnape100.livejournal.com/1522951.htmlWhat’s in the stocking
What They Didn’t Know
http://community.livejournal.com/grangersnape100/1218121.htmlWhen ghosts intervene
When I am old & grey
Whips and chains
http://grangersnape100.livejournal.com/1640160.htmlWhoops!
Wicked
http://community.livejournal.com/grangersnape100/1400851.htmlWine and cheese (or whine and cheese)
http://grangersnape100.livejournal.com/?skip=15Writing
Writing Harlequin
Year of the Snake
http://grangersnape100.livejournal.com/1616361.htmlZombie
http://grangersnape100.livejournal.com/1667221.html