Here are some websites that provide useful revision material for GCSE and A-level physics.
These are external web sites so there are no guarantees that the links will still work and use the content at your own risk.
www.physics.org, plenty of inspirational material from the Institute of Physics
Revision notes, from The Student Room
The Physics Classroom, an American site but with some useful material
Waves, mainly at A-level
Mechanics, from the Berlin High School
The Feynman Lectures on Physics Nobel Prize winner Richard Feynman (1918 - 1988) did much to popularise physics. These are undergraduate lectures but will interest anyone with a passion for physics.