This can't be seen outside of the US, but I figured that whoever lives in the US may be interested in this. http://www.slashcontrol.com/free-tv-shows/batman-the-animated-series/season1 It's just the AOL site where they have tv shows and movies. Free, just want to make sure that is clear.

Not sure if this is available outside the US, but the old "Kids WB" block has returned as a website, showing Batman: TAS, Batman Beyond and Static Shock (among other classics, like Thundercats):
http://dcbeyond.kidswb.com/video/

Batman: The Animated Series was always my favorite cartoon based on a comic, (the X-Men cartoon was also pretty high up there). It was actually pretty damn dark for the time, compared to the kind of stuff you see in children's cartoons nowadays.
Batman Beyond was also an amazing show, and although people really love to dog it I still really like The Batman. It had interesting takes on the different villains. Batman: The Brave and the Bold, the newest show, revisits some of the camp of the Adam West Batman series, but it's still pretty damn cool.
Overall, I think Batman's been treated pretty well when it comes to animated shows.

I just watched an episode of The Brave and the Bold on YouTube, and was laughing my ass off. Legend of the Dark Mite, I think it is.

AFAIK, it is a comic mini-series, not an animated one.