I already had build automatically turned off.

What actually did help was reverting to Eclipse 3.8 (Indigo) instead of Juno. I'm not sure if this is universal or just my system, but Juno is dog slow compared to Indigo, the different is night and day. I still like Sublime Text 2 over Eclipse, but Eclipse 3.8 is at least reasonably fast while Juno is incredibly slow (for me).