Justice League Unlimited
If you're a comic fan and you've never watched _Justice League Unlimited_ , it's highly recommended. From it's depiction of what Batman should be, to a version of Hawkgirl that far spaces the comics iteration (in fact if there was a comic based on this version of Hawkgirl, I'd subscribe in a second), to the hilarious comedy provided by The Flash (played by Michael Rossenbum (Smallville's Lex Luthor)) the show just shines. Seasons 1 and 2 are available in DVD right now, go pick them up.