Good books to learn more about microcontrollers / electrical engineering? I've bought the Arduino starter kit with the project book and I'm about half way through and addicted. 

As I go through the projects I wish they would go into more detail on the electrical components, and other things such as Ohms law. 

The question here is do you have any suggestions for books to read for the purpose of gaining a better understanding of microcontroller programming/engineering, from a beginners perspective?

Ideally I would like a book that can be read cover to cover in my spare time (more abstract concepts, instead of problem&amp;answer type books).
The newly updated 3rd Edition of "The Art of Electronics" by Horowitz and Hill is a great text/reference, worth every penny of its $80 price. It has a very practical approach and requires only high school math. I have been working with electronics for longer than I would care to admit and it teaches the subject the way I would like to have been taught.