Comment Online circuit tutorial (Score 5, Informative) 301
Try:
http://www.allaboutcircuits.com/
This has some good lessons describing the prinicples behind circuitry, and suggests some experiments to try. Best of all, it's free!
Historically, there have been a LOT of undefined x86 opcodes that cause the cpu to shit all over itself, stomp memory, elevate priveleges, etc.
Citation required.
The trouble with doing something right the first time is that nobody appreciates how difficult it was.