Hyperion is an opensource 'AmbiLight' implementation controlled using the RaspBerry Pi running Raspbmc. The main features of Hyperion are:

• Low CPU load. For a led string of 50 leds the CPU usage will typically be below 1.5% on a non-overclocked Pi.
• Json interface which allows easy integration into scripts.
• A command line utility allows easy testing and configuration of the color transforms (Transformation settings are not preserved over a restart at the moment...).
• Priority channels are not coupled to a specific led data provider which means that a provider can post led data and leave without the need to maintain a connection to Hyperion. This is ideal for a remote application (like our Android app).
• HyperCon. A tool which helps generate a Hyperion configuration file.
• XBMC-checker which checks the playing status of XBMC and decides whether or not to capture the screen.
• Black border detector.
• Generic software architecture to support new devices and new algorithms easily.

More information can be found on the wiki.

The source is released under MIT-License (see http://opensource.org/licenses/MIT).