For me its got to be Bad Boys 2, the scene where they go to the bad guys mansion and then blow it up. It has lots of bass, gunfire whizzing around etc also. I have seen ALOT of films and this is generally up there with the best for sound.
However I also really like the scene in House of Flying Daggers, the beans being thrown against the drums.
Another good one is the original Jurassic park, espeically the scene where the smaller dinos coming running accross that field.