In a happy story, the AP recently reported on I Found Your Camera, a website that since February has been posting "orphan pictures" culled from lost digital cameras and memory cards in hopes of getting them back to their owners. The founder of the site, Matt Preprost, was inspired by an entry on PostSecret about a camera found at Lollapalooza. So far, I Found Your Camera has had a high success rate—out of the 60 or so lost devices whose photos have been posted, 8 have been reunited with their owners.
I Found Your Camera isn't the only site that's worth visiting if you've lost (or found) a camera. The forum site Camera Found is straightforward, with more in the way of camera descriptions and less in the way of random strangers posing in front of soon-to-be-misplaced lenses (this also makes it much less entertaining). Places like Craigslist probably remain the most popular place for attempting a reunion between people and their property. (Making sure that all electronics have a cell phone number or email address on them couldn't hurt either.)
Of course, when it comes to the Internet and strangers, all bets are off. Back in 2006, "Judith," a woman who had lost her camera while on vacation in Hawaii, created a (now offline) blog that tried to re-create her shots using the many Hawaii photos uploaded onto Flickr. She got lots of press, and was even contacted by the Canadian family who had found the camera. Unfortunately, when push came to shove the finders showed themselves reluctant to actually return the lost property—they said that their 9-year-old son just loved it too much to part with it.
The family, dubbed "the Bad Samaritans" by the website Boing-Boing, did return the expensive camera in the end, but only after the National Park Service and border control got involved. Goes to show that blogs can't solve every problem in the world, I suppose.