Moodlight is a light, which changes it's color gradually. Check out the video to get the idea:
The light can be controlled with a computer, but the light doesn't need to be connected to a computer all the 
time, only when the user is making 
changes to the color patterns or the speed of the color change. 
Here's a screenshot of the control application: 
How does it work?
The brains of the light is a Microchip PIC18F2550 microcontroller, which stores colors and other settings in 
it's EEPROM. The microcontroller also receives color updates from a computer and drives the 3 colors using the PWM 
method. The light is using the highest power RGB led I could find as the light source, a led from 
Lamina Ceramics, the Atlas RGB led. 
The project shares the PCB and the firmware with my other USB project, the 
USB oscilloscope.
Because I gave out these lights as christmas presents, the software has to run also on Windows. Thus 
I've decided to write it using C# so that it can be run on Linux (using Mono) and on Windows.
Downloads
 - Firmware running on the microcontroller. A MPLAB 7.51 project containing 
the sources and the compiled .hex binary. (Also for the oscilloscope project.)
 
 - Software running on a computer. A Visual Studio 2005 project containing the 
sources and compiled binaries. (Also for the oscilloscope project.) 
 
 - PCB file to be used with the ExpressPCB software.