Well Monster and 20th Century boys have already been mentioned. So here's one of my favorites that is not very well known but I've seen at bookstores.
Kurasagi Corpse Delivery Service - a group of students graduate from a Bhuddist college and realize that their education didn't actually improve their chances for employment. So they instead turn to their special abilities, one can dowse for corpses, one can speak to the dead, one is an awesome computer whiz, one can do embalming and one can...channel an alien through a hand puppet.
Very morbid, very funny, sometimes sad, very episodic as they essentially travel around helping the dead achieve their final wishes.