Full Metal Panic Fumoffu, Golden Boy, and GTO are probably the best that I can think of. They make me want more after I finish the series.

Ranma 1/2 and Azumanga Daioh are pretty good, too.

However, I have to say Sailor Moon Live Action is hilarious. The costumes, the acting, the action scenes... I cracked up so much on how corny they were.

Those Who Hunt Elves 1 and 2 were funny, too. Not as funny as the above, but entertaining enough.

Oh yeah, I can't forget about Project A-Ko. My friends and I laughed non-stop when watching that one.

Love Hina was also good... A nice romance comedy.

Kyou Kara Maou and Midori no Hibi are funny and are nice series. I would feel better about Kyou if they had more females as main characters, to make a more balanced cast. Midori no Hibi felt a little short.