My first experiment with this aren’t really worth mentioning, so I combine it with a later revision.
I once saw an animation which created this really cool Pollock-like painting using the draw-class and the bitmap-class. (was something like this: http://stamen.com/projects/splatter). This started a project to create something similar.
For my first projects I wanted it to be [...]

I revisited the SoundMixer.computeSpectrum() class and tried giving it another twist. I also tried to find a way to make flash react only when a certain peak occured. I abandoned the project for something else before I could add some graphical element to it.
Song: Simpsons OST - Spiderpig
URL: http://www.mauricemelchers.nl/experiments/06_equalizer/spectrum2.html
Date: 2008

My first actual attempt with playing with the SoundMixer.computeSpectrum() class of AS3.
I did some playing around with how to use the numbers that came out of it. I intended it to be something small like a widget so it could be put in a profilesite or a blogpost or something…
Song: Daft Punk - Harder, Better, [...]

This isn’t really a live spectrum analyzer. I imported a song in After Effects and converted it to keyframes.
These keyframes could then be copy-pasted into Actionscript into one big array.
They way you use these numbers is all up to yourself ofcourse…
Song: Simpsons OST - Spiderpig
URL: http://www.mauricemelchers.nl/experiments/06_equalizer/spectrumHand.html
Date: 2007