Sparkfun also has an exceptional write up on how to get into the microamp ballpark: http://www.sparkfun.com/tutorials/309 http://www.sparkfun.com/tutorials/309

Sparkfun also has an exceptional write up on how to get into the microamp ballpark: http://www.sparkfun.com/tutorials/309 http://www.sparkfun.com/tutorials/309 The article's try and see approach is very detailed and a great read for anyone looking to get into prototyping with AVR for battery based projects.