I ran across this article at Gizmodo:
A Creepy Website Is Streaming From 73,000 Private Security Cameras
It discusses a website, www.insecam.com that purports to show 73,000 private IP cameras that have failed to change the cameras default password. I was able to view cameras with mixed success, some failed to show, some showed, all were slow to populate.
There's also an interesting post on there from Jeremy which links to a YouTube video about hacking security cameras:
Black Hat 2013 - Exploiting Network Surveillance Cameras Like a Hollywood Hacker - YouTube