This is my variant of i2c-tiny-usb from Dr. Till Harbaum. You can find the original project on his homepage:
http://www.harbaum.org/till/i2c_tiny_usb/index.shtml
I modified the PCB schematics to fit my requirements and created a nice case for it. The actual firmware for the ATtiny is exactly the same. Instead of the ATtiny45 I used an ATtiny85, since it's cheaper nowadays.
The PCB and the case are licensed under CC-BY 3.0:
https://creativecommons.org/licenses/by/3.0/
-- Sebastian Reichel [email protected]