Neverwhere, Neil Gaiman
Anything by Terry Pratchett. Here you can find a guide of where to start. Any of the starter novels are good place.
High Fidelity, Nick Hornby

Runners up:
The World According to Garp, John Irving
American Gods, Neil Gaiman
Anansi Boys, Neil Gaiman
Good Omens, by Neil Gaiman and Terry Pratchett

Suggestions from Cel:
Dead Before Dark, Charlaine Harris
The Secret Diaries of Miss Miranda Cheever (cheesy hetero romance)
Carnivale, Elizabeth Bear
Anything by Lincoln Child and Douglas Preston (they write together as a team)