The ehaserl was the conference badge of the Easterhegg 2010 organized by the Munich Chaos Computer Club.
I was not involved in the circuit or board layout, but i helped out soldering and wrote three different firmwares for the badge to have an initial pool of example files for the conference participants.
By the way, when i say helped out soldering, i mean soldering three hundred of these – it was quite time consuming :)
- default: scroll nickname on LCD and flash LEDs if its dark
- bugger: morse “EH2010″ via LEDs and piezo
- monophonic: play any monophonic ringtones via piezo
You can find all layouts, source code, solder tutorial, etc on the badge page.