Any anime over 26 episodes (I'd even go so far as to say over 13) would utterly fail as a movie, even with a trilogy.
it has actually been suggested multiple times on both pages lolI have no idea why Attack of Titans hasn't been suggested yet. The setting is European so Hollywood shouldn't have any casting problems bar mikasa, maybe. No shitty cheesy humour to translate over, and awesome as fuck action sequences - Human v/s Titan, Titan v/s Titan. I mean just imagine the first invasion arc on the silver screen culminating with Eren's first titan transformation.