When the Nolan films run out of steam(ie, when he quits doing them and they bring in other directors and fuck everything up again) and they once again reboot the series, I think it would be really cool to have it set in 1939. The animated series kind of had that look, but in a modern setting, and it worked really well. It'd be awesome to see a "period" Batman film. And I know they'd never do this, it's just wishful thinking, but what would be even cooler is if they did it in black and white, in a film noir kind of style. You know, similar to Sin City. A really dark, moody B&W Batman set in the time that the comic debuted, that's my dream Batman movie.