Elliot Williams is a Ph.D. in Economics, a former government statistician, and a lifelong electronics hacker. He taught himself to program microcontrollers long before there was any such thing as an Arduino, and loves to spread the knowledge. Most recently, he is author of the Maker Media book "Make: AVR Programming, Learning to Write Software for Hardware", which is chock full of microcontroller-programming tidbits and thick enough to stun a rhino.
Programming AVR Microcontrollers in C - O'Reilly Webcast