Let's see...
Jungle wa Itsumo Hare Nochi Guu is good, as is the subsequent Deluxe and Final OVAs, which show the adventures of Hare, his drunkard of a mother and a strange little girl by the name of Guu who can apparently eat anything or anyone, and has some kind of alternate dimension inside her stomach. Just trust me, it's hilarious.
Bo Bobo is another hilarious one, about a guy who fights with, of all things, his nose hair. He fights a gang of thieves that steal people's hair, run by a bald guy who still lives in his mom's house. The whole thing is kinda bizarre, but really funny.
Beck is about a boy who joins a rock band struggling to hit it big. Much more intersting than it sounds, but not exactly full of martial arts action, if that's your thing.
Bleach is probably a good one for naruto fans. It's about a boy who by accident becomes a shinigami, hunting down evil spirits called hallows with a giant sword.
Gantz is another good one for action fans. It's about a teenage boy who died, but was given a second chance at life, the only catch being that he, along with other recently dead, has to play a life or death game against "aliens" with the help of special weapons and a suit which multiplies the wearer's strength.
Gokusen is very similar to GTO, but quite a bit better in my opinion. Instead of a guy who was a former biker gang leader that becomes a teacher, it's a woman who was raised in the yakuza. And if you've never heard of GTO (Great Teacher Onizuka) you'll probably want to check that out. It kinda got stale for me after the first dozen episodes or so though. It was pretty good, just should've been shorter.
Well that's just a few from what on my hard drive for the moment. I can look through some of my "archives" if you want some more.
Archived topic from Iceteks, old topic ID:2876, old post ID:25356