READING
PHYSICAL COMPUTING. SENSING AND CONTROLLING THE PHYSICAL WORLD WITH COMPUTERS.
Dan O'Sullivan and Tom Igoe
Muska & Lipman/Premier-Trade; 1 edition (June 2, 2004)

This book (bible) covers issues such as:

- the basics of electricity
- how to compile your basic shopping list for electronic supplies
- using microcontrollers for inputs and outputs
- making connections between programming languages and the physical world
- network/communication
- sensing and making movement.


REFERENCE LINK

Co-author Tom Igoe's excellent website on physical computing:
http://www.tigoe.net/pcomp/index.shtm