I was reading this question about destroying safety data from CD's and I was about to recommend in a comment to use this laser in form of a lighter that is >2000 times more powerful than the sun in ...
Is there any reason why running a lengthy ddrescue session on a scratched DVD would be bad for the DVD drive? Something like overheating or straining of certain components?
A friend of mine has a DVD with a crack "its a crack straight through it, about two centimeters on each side of the middle circle", he says. I suggested toothpaste, will anything else work?