Reviseomatic A simply massive site - start here

Edutek A comprehensive and varied website with lots of project ideas

555 Circuits A lot of 555 circuits to play with

Electronics 2000 Big turn of the century electronics project

Electronics Lab Some good project ideas

Electronics Teacher More tutorials etc

Electronics Tutorials Comprehensive basic electronics tutorials and revision for students and beginners

Hobby Projects Lots of projects and tutorials

Resistor Guide An utterly comprehensive guide to absolutely everything you would ever need to know about resistors, the resistor equation and much more