Since it is a MacBook Air it has "Back to my Mac" on it. If the laptop is used to go online you can login into your mac and turn the cam on and see who is using your Mac. Their was a thief caught not to long ago using this.
http://www.apple.com/dotmac/backtomymac.html
http://www.news.com.au/couriermail/s...003402,00.html