I can't think of a better example of the use of a whammy pedal than Pantera... for a clear example is "becoming", Dime played a riff where the last note was pitch shifted very high, but it was only one note.

My POD XT has the bender (based on the whammy) and it makes awfull noises when you play a chord (bare chords for example) cause it scrambles the signal so bad that the only thing you get it's this weird robot like sounds flying around.

Try making some frases were you hit the pedal at the same time with a single note, and have fun with it... make it fast and furious (never mind the movie) or a slow melow progression with it.

Check too Joe satrinani's "in flames" as a very good and very musical way of getting the most out of your whammy, and if you can see the G3 live in tokio version... well you'll run to your whammy.