Thanks to Kottke for pointing this out...
"House keys left out on table + telephoto lens at a distance of 200 feet + SNEAKEY key duplication software = perfect working copies of your keys. Eep. The system also works with crappy cellphone camera photos."
So, this means from a physical security perspective, it's probably best not to leave your keys sitting in plain site - especially if they are keys to anything remotely valuable!
Also noted by Schneier last week here.
