http://www.citycom.gr/electronics/downcircuits/79.zip
http://www.4qd.co.uk/ccts/curli.html
http://www.imagineeringezine.com/PDF-FILES/powerlos.pdf
The theory behind wire, resistors, capacitors, inductors and semiconductors as components.
http://www.hills2.u-net.com/electron/componen.htm
http://www.mitedu.freeserve.co.uk/Circuits/Misc/maggun.htm
Tutorials Fundamentals of Digital Logic
http://www.williamson-labs.com/480_logic.htm
This is a basic introduction to the concepts of charge, voltage, and current. Discusses Coulomb's Law, Ohm's Law, and power. Includes graphics and animations.
http://www.swansontec.com/set.htm
Signal Integrity workshops taught Dr. Howard Johnson
http://www.sigcon.com/