Cammster is this kind of web service, offers a simple way monitors your room, you only need things are, a webcam, an account of Dropbox or Rapidshare, access internet, register an account on Cammster. After that, you can hook up your Dropbox or Rapidshare with your account.
How does it work? Actually, Cammster uses a web based alarm system, it will take pictures when it detected motion in your room. You can choose a way to receive alarm, like email, sms, store picture in Dropbox or Rapidshare.
After all done, you are ready to use this service. You have to turn on your computer, webcam, and enter your account, click "Run cammster now" button. All done. This is a good way to monitor your room while you are on travel.
The basic service is free, it also offers paid functions.