Yes, toothpaste or soap quite often works. The problem is the laser reflects strangely off scratches, but if the scratches are filled in with opaque particles (such as toothpaste or soap) then the CD player's auto-correction should be able to deal with it. For this reason of course you have to be careful not to wash ALL the toothpaste/soap away, otherwise it will have no effect at all!
If you're particularly attatched to the CDs, there are some music shops / game shops that you can take damaged disks to and have them repaired for a small charge :) x x