Bobobo-bo Bo-bobo is as random as it is funny, many people may not concur with me because this is one of does "Either you love or hate it" anime/manga. FLCL was also funny.

Funnies Manga
 

I saw an anime call Rizelmine that it was really really funny! :P

I've read the manga which was pretty good.

I downloaded Excel Saga the other day and watched it up to episode 6, i dont know what to say other than it wasn't good. I was bored with every episode. Deleted it of the hard drive.

Slam Dunk had many funny moments

I don't know if anyone has seen it but, Kanokon was pretty funny. It has fanservice so if you don't like that you probably won't like this anime.

Ill look into it.

Excel Saga is funny as hell. You might have to have a bizarre sense of humor to really appreciate it though. Golden Boy is pretty funny too, and Cowboy Bebop. I always thought the GTO comics were really funny, but I don't think the humor translated that well as an anime.