Put your computer into rave mode!
A fun little tool to make your Mac screen light and keyboard light react to sound. A great addition to any party.
Just download and install Max/MSP (free), download and open audeyoe_ravemode.mxf ($1), and have fun.
You can set it to react to incoming sound from the built-in microphone, or play an audio file from right there in the app. Set the sensitivity, and choose whether to control the screen, the keyboard light, or both.
Accidentally set your screen brightness to zero and can’t see? No problem, hit the spacebar to stop Rave Mode, and it’ll set your screen to the brightness it was when you opened the app.
See it in action: