the funniest one i have seen would be School Rumble. its about a bunch of 'ordinary' high school students and their problems, mostly about love. every characters personality is well defined and the story is very original. well plotted.
the other one would be Yakitate Japan! its an anime series about 'bread making'. i know it sounds like a turn off, but dont underestimate this little piece of work here. its got every element a good comedy needs. drama, hilarious exaggeration, and even a little educational (im turning you guys off again aint i?)
and the last would be Keroro Gunso. a frog like alien helding a family (its more the other way around...) under hostage while planning to take over the world....though i dont think they have it subbed/dubbed in english, not yet anyway. its quite big in Japan now.