There are a few solutions available for tracking a laptop in the event it is lost or stolen but today I read about an open source project and thought I would share it. You can read all about it on the site but its free (hence open-source) and you need not worry about your personal privacy with it installed. Only the end user can track the locations due to the nature of the program...so no one else, not even the group running the project can track your gear.

This is the site: http://adeona.cs.washington.edu/

There's no reason you couldn't install on a desktop PC as well if you feel the need. There is no fool proof solution but a step taken is better than none at all.