Phantom 2040

Phantom 2040 is probably the best animated action-adventure series I've seen. It doesn't cater to a low-intelligence audience: you've really got to watch this, and watch it carefully, to follow everything that's going on. Lots of intricate inter-plotting of episodes and characters, somewhat sympathetic bad guys (Ron Perlman's Graf in particular, one of the "grayest" villains ever), funky artwork, and a well-developed future society (compare it to, say, "The Magician" (1998)). Hopefully someone will carry this in repeats at some point (Sci-Fi Channel, maybe), because it's a show that should have stayed on forever.