I haven't had an opportunity to lose my digital camera yet, but I'm ready. Here's my tip on that:
If you have a computer, open your favorite word processor and make a nice big page of your name, address, phone number, playa name, etc. so it fills as much of the screen as possible. If you don't have a computer, write it all on a sheet of paper in thick marker to fill the whole page.
Now take a picture of the screen or paper so you can read it on the camera screen.
Some cameras have a feature where you can "lock" pictures against accidental deletion. Do that with this one. If you can mark it as a favorite, or move it to be the first picture in the camera, that would be great too.
That way, if someone finds your camera (or even just the memory card) they at least have some way to track you down.
May your deeds return to you tenfold,