Ditto to Veign and the CD shredder. I bought one and gave my old shredder to a friend.
I did a normal delete of all the files. Then used eraser to do a seven time 0/1 write and then used it to write pseudo random data to it. Once I did all that, I realized that CF and USB sticks could be ripped open and the memory chips ripped apart with a pair of pliers.
I did the same with the hard drive platters. It's all good practice for when the US Government becomes a totalitarian state in a few years and I am deemed a member of the rebel alliance.