one cool trick. play a note, any note, say, low g. *Slowly move the finger playing that note up the
fret board, while dropping the whammy bar at the same time. *so, pitch on the fret board is increasing, while the whammy is lowering the pitch. *Makes for a really cool growl sound, if you can sync the two techniques together.
In the end, when u do them both at the same time, the pitch of the note stays almost the same: sounds like a suffering animal. *turn the distortion up!
Also, if u face the whammy to the outside of the guitar, over to your far right, and just tap it towards the body of the guitar each time u play a note (i like using notes from harmonic minor), u can sound real freaky! *TAp the bar down with each note very lightly, sounds like an east-indian type of tone. *Really cool, vai does it all the time.