A while back I came across an article about a website that tries to reunite lost photos with their owners. People who come across cameras, memory sticks, or photos are asked to upload a few of them onto the site with information such as location, date, or other specific details that may be recognizable by the owner. These photos are public to everyone on the Internet and the goal of the website is for people to browse through the pictures and to connect the photographer back to the photos.
While I can appreciate the spirit of the site, as a security person, I'm very skeptical about introducing a found memory stick or photo memory card into my computer. As noted in the ISTR XIII, memory sticks (or USB thumb flash drives) represent a serious security concern because they can be entry points for malicious code into a computer or network. As with the floppy disks of the past, these USB drives can be infected with malicious code, such as viruses, worms, or Trojans, which can propagate when inserted into a computer. A user who finds this type of removable drive may unwittingly copy the infected files onto his or her own computer and, if the computer is connected to an enterprise, may potentially infect the network. Also, since many USB drives have huge storage capacities, a small infected file among hundreds of MB-sized photographs would be difficult to detect.
As part of any best practices, be suspicious of introducing any foreign media into your computer, especially if you don't know where it came from. Some lost things may need to stay on the island!