The LongPixel is a chain-able board that turns a strip of Analog RGB LEDs into a giant, digitally-controlled LED. It is able to drive 12-24V Common Anode RGB LED strips (the kind that have +V, R, G, and B wires). By using the WS2801 LED driver chip, multiple LongPixels can be chained together and treated as a "strip" of digitally addressable super-LEDs. The LongPixel can work with just about any platform that supports SPI communication, including the Arduino, the Raspberry Pi, and our AllPixel LED controller.
For more information, check out:
...and the wiki: