Nothing too "out there"... just a decent, funny story.

Straight Man by Richard Russo

Skin Tight by Carl Hiassen(All his books are funny but this is his best)
Straight Man-Richard Russo
Handling Sin-Michael Malone
A Confederacy of Dunce-John Kennedy Toole
Anything by Tim Dorsey

I think one of the funniest books I've read is "Youth in Revolt" by CD Payne. One of a very few books I've voluntarily read more than once. A large part of it is the sexual fantasies and experiences of a 14-year old boy, so be aware of that going into it.
I read A Confederacy of Dunces, and while I could appreciate the bizarreness, it just wasn't all that "funny" to me.

I saw this thread title and immediately thought Youth in Revolt as well. Very funny book, though the second book was pretty mediocre.

I'm a big fan of I Love You, Beth Cooper by Larry Doyle. It was my favorite book that I read last year. http://www.amazon.com/I-Love-You-Bet...2149434&sr=8-2

You're the first person I've ever met who's heard of that book! Awesome! It's one of my favorites. It's loaned out to one of my friends right now.. it's my second copy.

Big Trouble made me laugh out loud.

I plan on reading Beth Cooper and Youth in Revolt soon.

Good Omens by Neil Gaiman,Terry Pratchett

http://en.wikipedia.org/wiki/Good_Omens

Hilarious! unless you are easily offended by religious humor.

i'll second A Confederacy of Dunce by John Kennedy Toole. i laughed on practically every page.

At Swim-Two-Birds - Flann O'Brien
Pale Fire - Vladmir Nabokov
Duluth - Gore Vidal
Nothing Like the Sun - Anthony Burgess
Five Novels - Ronald Firbank
Love's Labour's Lost, A Midsummer Night's Dream, Twelfth Night - William Shakespeare
The Wicked Pavillion - Dawn Powell
Almost anything by Samuel Beckett.

Thanks for the suggestions everyone. so far, I have read "Straight Man" and "I Love You, Beth Cooper" and loved both of them. "...Beth Cooper" is the best book that I've read in a long time.

I recently started "Youth In Revolt" and I'm liking that so far too. After that, I'll either read the next chapter in the Nick Twisp saga or move on to one of the other selections in this thread. I'll probably throw in another Stephen King in between those.

Thanks again, everyone.

I can always recommend T.C. Boyle's The Road to Wellville. It's the only book I can recall that actually made me laugh out loud.

Not Catch 22. Don't let anyone tell you it's funny.

Any of Christopher Moore's books, though I'm particularly fond of "Lamb" and "A Dirty Job".

I thought Catch 22 was hilarious.

I'll second Good Omens; very funny book.

Forrest Gump.

I will second Christopher Moore. Lamb was a Laugh out loud book and my personal favorite with Coyote Blue a close second. Dorsey books are great as well particularly if you like Quartino films meaning a bunch I weird characters many are really evil and ultimately get whats coming to them when they cross paths with Serge Storms. I personally love dark comedies and always look forward to new books by Moore and Dorsey.

Moore is a great comedy writer. All the books I've read by him have made me laugh out loud with the exception of his first novel. He would make a great writer for SNL if hired.

Catch-22 has an interesting arrangement. Instead of the episodes being told in chronological order, they are told in order of funnyness. The funny episodes are at the beginning, and the creepy and disturbing episodes are at the end.

The stuff towards the beginning is hilarious. The stuff towards the end makes you feel like you've been slapped. I liked it a lot.

Early Richard Price is very funny:

Ladies Man and The Wanderers in particular.

I also like Perv - A Love Story by Jerry Stahl,

And I think Portnoy's Complaint by Philip Roth is hysterical.

Of course all of them have some sick sexual content involved.

Three of the funniest books I've ever read are White Boy Shuffle by Paul Beatty, King Dork by Frank Portman, and The Princess Bride by William Goldman.

David Eggers' Heartbreaking Work of Staggering Genius had me laughing out loud frequently, although the book's subject matter is pretty weighty.

Naked Gun 21/2 - its so silly and slapstick but even on my own and am left in a state of uncontrollable laughter throughout!

The series of Fletch books by Gregory McDonald are very good. Chevy Chase did a good job but novels are much better.

Job: A Comedy of Justice by Robert A. Heinlein is great.

The Hitchhiker's Guide to the Galaxy series by Douglas Adams are classics.