This method is the most extremely effective way on bringing back unreadable and heavily scratched CD's but a word of CAUTION! it is also the most risky and dangerous!
You need the following to begin with.
1. A Gas Stove
2. Cotton Towel
3. Pot with 2 inch of water.
Step 1: Position the fork into the CD.
You need to insert the two tooth of the fork into the center of the CD.
Make sure that the fork doesn't change the CD's contour too much, and it must be straight and even.