This is a very nice video of audio/video integration. The video was apparently made in Adobe AfterEffects. It looks like it makes heavy use of Lissajous curves being created from various portions of the audio (though I could be way off on this). You can use this sort of method to play around in PD by having oscillators (functions) manipulate the (x,y) coordinates of a point in the gemwin.

Forss – City Ports from Eric Wahlforss on Vimeo.

Here’s a much simpler example of Lissajous curves using audio. This is a modular synthesizer plugged into the inputs of an oscilloscope set to X/Y (or Lissajous) mode. You can see the change in audio relate directly to the change in the image.