These are simply ATTiny45 based USB devices based on the V-USB circuits and drivers developed at Ob-Dev. I haven’t decided what to do with these yet but the many ideas include a prank keyboard dongles like the capslocker or a keyboard to continually hit F1 or Delete to ensure the bios comes up.
My original idea was to have it generate and remember random passwords so you don’t need to type in your 63 char password for the wireless router every time someone comes to visit , simply plug in the dongle and it will type it for you. There are other non keyboard ideas as well such as a simple data logger that converts voltage, temperature, (insert random digital sensor here) to a comport that responds to commands or simply pushes data at a specified rate.
I see Sparkfun have done a nice version of this PCB with some similar ideas. Theres is called AVR Stick