This is what they had to say about the kit:
"Spoke POV is an easy-to-make electronic kit toy that turns your bicycle wheel into a customized display! The project includes a free schematic design, open source software for uploading and editing stored bitmap images, and a high-quality kit with all the parts necessary to build your own.
Specifications and Features:
30 LEDs on each side (22 for BMX) x 256 radial pixels
Runs on 2-3 AA batteries for 10 hours or more, assuming 3000mAh alkalines and 50% image coverage.
Can run on rechargable NiMH AA's
Comes with high-brightness red/yellow/green or blue LEDs
Automatically shuts off after 3 minutes
wxPython based software runs on any Linux or Windows or Mac with Parallel port or serial port
Design is all through-hole parts, perfect for a first time kit builder.
With one spoke, total persistence at 15mph. Two spokes, 10mph. Three spokes, 7mph. (Assuming a mountain bike wheel). Looks cool even if not completely persistant.
Great for safe riding at night, provides excellent side visibility.
Playa-tested!
Make your own by following the step-by-step guide on Instructables