Do you like to mod computers? This project might be really great addition for you next cool case. It is a USB controlled RGB LED UV meter. USB information is processed by PIC18F2550 which then sends signals to TLC5940 – a 16 channel PWM LED drivers (3 units for each color).
PIC microcontroller has a native USB interface you can run it easily by adding Open Source Framework for PIC18F USB. Probably most fun part is a host application that is written in Visual Studio C# 2010 and runs under Windows 7. To display UV information on LEDs you actually need to track music information. This is done by using another API that can do lots of thing with music information. Everything is wrapped in to nice GUI where you are able to select several parameters like damping speed, fade OFF speed and colors. Final effect looks really great – worth trying.