Something that would make it to every photo you took via EXIF information. I think it would be very useful if we could use PTTools to define a small text signature (ex: "This camera belongs to John Doe, 1000 - Planet Earth, North Pole: john_doe@earth.org").

This way, if your body gets stolen and assuming there is a 50% chance that it ends in hack ignorant hands, you have a meaningful chance to see some traces of it surfacing the Web in the form of pictures taken with that camera.

P.S. - I posted here because my searches for feature requests threads were fruitless.