Anything by Chuck Palahniuk is a fast, delicious read if that's the sort of thing you're looking for. This is the guy who wrote Fight Club, if you didn't know; I'd recommend Lullaby and Choke.
If you want some denser material and a serious mindfuck, check out House of Leaves. I'm not too far in yet, but looking at it, some of the later pages dissolve into crazy scribbles like they were cobbled together from notes. Critics call it post-post-modern, and it's pretty engaging so far. The story itself is sort of hard to describe; very metafiction. It's about a documentary where this family whose house is bigger on the inside than the outside, and growing, and unleashing weird things from the labyrinth inside--inside a novel, inside footnotes by this guy who found the novel, inside footnotes by the editors, all of whom have stories unfolding at the same 'time'. It's as confusing as it sounds, but still really good.
If you like fantasy, check out Johnathan Strange & Mr. Norrell, by Susanna Clarke. Starts out slow, but gets crazy by the end.
If you're into sci-fi, check out Calculating God. If your 'book' doesn't have to be a novel, check out 'Beyond AI'; talks about how AI will be developed in the realistic, corporate world we live in, and how it will affect us. If that grabs you, pick up The Singularity is Near by Ray Kurzweil, though I'd suggest reading the summary and getting out quick; he's really dry and long-winded and statistic-driven, but that's to support his pretty massively epic thesis that the entire internetz are gonna crash together soon and form what he calls a Singularity.
Hope this helps
edit: I second World War Z and Life of Pi. Awesome books, and if it's for an english or writing class, you can analyze how the authors uses interview-notation to tell a broader narrative
