A link to this was posted by Nick Baker (known from Animal Planet) on Twitter yesterday. Basically, it's 24 photos, and you have 30 seconds to spot the one fen raft spider that's in each of the photos.
But it's not just a game, it's science! Some of the spiders have bright bands on their sides, others are all brown. By having people playing this game, the guy who made it is trying to determine which spiders are better camouflaged, and which are likely to be lunch.
Ready? Enter the
Spider Spotting Challenge!
(And yes, this is obviously not for people who can't stand the sight of spiders.
)