I've been messing around with various methods for presenting FFT information recently and this screencast is based on some of these ideas. This particular screencast uses impromptu's analysis audiounit to retrieve fft data which is then loaded into an image. The image is then blurred using a gaussian filter. The image data is then pulled from the image and converted for use in vertex and colour arrays in OpenGL such that rgba is xyzw and rbga.
The result is surprisingly organic.