Sayonara Zetsubou Sensei

[Tetsu (Doki Doki ~♥), WRRRRY!]

Revolves around a very pessimistic high school teacher named Nozomu Itoshiki who tries to hang himself on a cherry blossom tree. Despite his best efforts, he is saved by a very optimistic girl known as Kafuka Fūra. She explains to him that it is simply unforgivable to hang himself on such a nice day, especially in front of such beautiful trees. She decides to nickname Nozomu "Pink Supervisor," offering to pay him fifty yen to do so. After having enough of the strange girl, Nozomu bolts to the school and starts his homeroom class, but the attempt was in vain as he finds that the girl is one of his students.

[Andy]

I've heard good things about this, though never really persued it. Is it really good?