OMG Catscratch is one of my favs. Earthworm Jim is one of my favorite cartoons and I don't see people talking about it very often... I think it's underrated, it's very funny. Clerks animated is one of my favorite obscure cartoons also.
Fritz the Cat, The Nine Lives of Fritz the Cat, Wizards, Coonskin and Hey there good lookin (more of the novelty of it for these two though), Rock and Rule, Mission Hill, and Dr Katz Professional Therapist.