Just ran a search on google. I found your AVR Keylogger. But too many hits when I tried using PIC.
This keylogging is kind of interesting. Seems to be divided into three main groups; spies(thieves), parents/spouse, and anti-keylogging. Seems to be one of those barely legal devices. I'll try and remember to search next time I visit Hack-a-day, Make, I-Hack or similar sites and see what turns up. Pretty sure I've seen this before a few times, just wasn't interested.