Because both The Lego Movie and 21 Jump Street were hilarious and way, way better than expected, I finally decided to check out Phil Lord & Chris Miller's old animated MTV series, and it is brilliant:
https://www.youtube.com/watch?v=-XBlrAxPtAw
It's about a high school populated entirely by clones of dead historical figures (Lincoln, Joan of Arc, Gandhi, JFK, Cleopatra etc), and is a spot-on parody of overwrought teen angsty TV/films, is very funny, and has an awesome theme song.

Do you have any other cult or would-be cult TV shows that you'd recommend that might have slipped through the net?