Today the camera on my Area 51 18 laptop quit working. Windows is telling me there is no camera detected. Is there a switch or keyboard shortcut where I could have inadvertently shut it off?

I don't know if it's related, but Device Manager is showing an "Unknown USB Device (Set Address Failed)". Dbl Clicking the entry shows:

Device Type: USB controllers

Location: Port_#0020.Hub_#0001

Device Status - Windows has stopped this device because it has reported problems (Code 43)  The USB set address request failed.