What did you do other than rotate the video and reflect it? Because, I have a feeling that a program could be made to take videos and automatically do this to them, and then you could have a whole library of these 
I was thinking the same thing.
Maybe Dylan should add a new mode to do the things you mentioned to display a type of visualizer other than (in addition to) what Free Ride gives.
Here are the things I did -- it's a copy of a post made earlier about it in the Steam AudioSurf forum.
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For those of you interested in how the Helden vid was made, this is what I did.
1] - Load up FRAPS
2] - Record AudioSurf Free Ride then quit.
3] - Start Sony Vegas Pro 8
4] - After importing video file into Vegas project media rotate it 90 degrees counter-clockwise and then drag it into the work area.
5] - Add plug-in "Mirror" in track effects to...mirror the left half of the screen (which was the top before rotation).
6] - Add plug-in "Cookie Cutter" in track effects chain as a circle and feather its edge.
7] - Add plug-in "Glow" in track effects and adjust intensity and the color to be effected.
8] - Add plug-in "Light Rays" in track effects and adjust intensity and angle.
9] - Render video to file.
There were probably some other, minor adjustments made as well (track motion) but I can't recall the specifics right now.
All told, it's not very difficult to do -- it just takes some of your time and patience to get things to look the way you like. I stress patience here because of the time you will spend waiting for Vegas to render the file. I always use two passes in the render process which gives better quality but the penalty is the length of time required. For example, the Helden video took about 1 hour to render while the Steppenwolf vid was about 2 1/2 hours due to the more elaborate effects.
Also, my machine is 7 years old -- a single-core rig. I'm sure a more modern multi-core machine with a much larger FSB than mine (just 400MHz) would take less time to do the same thing.
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I missed a step:
10] - And then you upload the thing to YouTube and let them crappify it.
