I love a good crossover, especially those that combine fandoms you're unsure would work but surprisingly do! Here are some of the few I've been lucky to come by.
Fandoms: Ugly Betty, Batman (Nolanverse)
Title: Betty and the Bat
Author: Piper
Link:
A3ORelationships (not necessarily romantic): Bruce Wayne/Betty Suarez, Daniel Meade/Betty Suarez, Bruce Wayne/Selina Kyle
Rating: T
Complete?: Yes
Words: 35,000+
Summary: At the end of season one of Ugly Betty, Betty finds herself in need of a new boss.
Why Read: Betty as Bruce Wayne's assistant, why wouldn't you want to? The only fic of its kind, crosses these two fandoms so well that makes you wonder why there aren't more of these (seriously someone write one, please do). I won't give much away but the story begins with Alfred interviewing Betty (one of my favorite moments), and from then on, Betty will not only be Bruce Wayne's assistant but confidant. It's a wonderful read.
Link to Sequel:
Betty, The Bat, and The Bird (incomplete, indefinitely but up for adoption)
Fandoms: Pride and Prejudice, Buffy the Vampire Slayer
Title: Borrowed Time
Author: Peapods
Link:
A3OCharacters: Mary Bennet, OC
Pairings: hint of Mary/OC
Complete?: Yes
Words: 1,000+ (one-shot)
Summary: She may be the one girl in all the world, but Mary Bennet has never really gotten much acknowledgement.
Why Read: It's true, Mary Bennet, didn't get much acknowledgement, which is why it is such a fascinating concept that she could have been a vampire slayer this whole time. The author does a great job of interpreting Mary's thoughts and actions, tying everything together nicely and keeping with the events that happen in P&P. Although the story works nicely as a one-shot due to the author's choice of style, a part of me would have absolutely loved for this to be a multi-chaptered fic.
Fandoms: Gossip Girl, Twilight
Title: The Vampire and the Socialite
Author: Vamp-by-Night
Link:
http://www.fanfiction.net/s/5115426/1/The-Vampire-and-the-SocialitePairing: Blair/Edward
Complete?: Yes
Words: 70,000+
Summary: Previously: Material Girl. Blair Waldorf's been banished...to Forks! A certain sparkly vampire better watch out, diamonds ARE a girl's best friend. No Bella.
Why Read: The title saids it all I think. The thought of Blair Waldorf in Forks is hilarious, and rightly so but it only makes this fic so much more enjoyable (in a good way) to read. Surprisingly it works well! The characters are spot on, and Blair and Edward's interactions are wonderful and amusing.