One day, I was blissing out, staring at the iTunes visualizer when it hit me that I could be a cheap bastard and simply record that playing one of my tunes and I'd have a video.
The next question was how... Turns out that the Quicktime player app can record your screen and soon, after a couple of false starts, I got a video of the visualizer running in full screen on my tune Polyphasic. Next, I used iMovie to attach the audio to the result (and get it all synced). After I was happy with that, I had to wait forever while the whole thing rendered and uploaded to youtube. The result: