Here’s a neat article about how to turn a mac’s external video port into a nearly free I2C interface that requires no drivers.
http://www.paintyourdragon.com/uc/i2c/index.html
Kurt
How coincidental… I stumbled across this today too. Guess I wasn’t the only one reading the wikipedia page 
25c I2C…Hard to go wrong there!!
- $400 to extend your AppleCare contract
Best Regards, Thorsten.
Or be like me and use one of the 37 expendable Mac logic boards video cards you have laying around.