At some point during a move my PS3 must have been dropped. It was out of warranty so there was no point in sending it in, and besides, everything seemed to work except that it wouldn't recognize any discs.
It was fairly easy to repair, but I needed a security torx driver. once I got it open I found out the the whole problem was that the data ribbon cable ha come loose. I put it back in, cleaned the blue-ray lens for good measure, and it works like new again.
There isn't much to the inside of a PS3 if you've ever seen the inside of a computer. If you are already out of warranty, have no fear of opening it up.