Guysoft shows us how to create a Bumble-b LED Matrix Computer Interface. I have never used a Bumble-b but for $17 how could you go wrong? It seams like one of the best ways to communicate directly via USB to a computer.

Via: HG Forum

"After getting my LED matrix to display messages, I wanted to make use of the USB port, and get the matrix to work as a USB device, this was much simpler than I expected. Once I had the code to control the matrix, it was simply a matter of copying it and using LUFA. LUFA (Lightweight USB Framework for AVRs) is a library that will let you get the Bumble-b to work as a USB device."