I found a unique website the other day called StolenCameraFinder – I lost my Sony A200 DSLR a while ago so I decided to give StolenCameraFinder a go to see what it could do for me.
In a nutshell, you upload a photo taken by the stolen/lost camera to the website. It then cross references a unique serial number which is found in the picture against a large database of serial numbers. If the serial number is found in the database, it could potentially mean that a photo was taken from your camera and uploaded online after it was lost/stolen.