In this project, we communicate with a Freescale MMA7660 accelerometer using the Atmel ATtiny85.
Here's the schematic:
I2C communication is done using the I2CMaster library from Peter Fleury:
http://homepage.hispeed.ch/peterfleury/avr-software.html
This project was also a test bed for me to get a feel for Atmel Studio 7 and the Atmel ICE debugger.
You can read more here: