Your laptop is missing. You're completely out of luck, right? Not if your laptop can phone home. Prey is a cross-platform security application that sends home pictures and location data when your laptop goes missing.
When your laptop goes missing Prey scans for open WiFi connections. When it can connect, either via WiFi or a hard line it will send you a report including the status of the computer, which programs are running, the active connections, a run down of the network location, a screenshot of the desktop, and if your laptop has an integrated webcam you'll even get a picture of the person sitting in front of it.
Prey can be set to trigger in two different ways. You can specify a URL for it to check, if the URL exists then it sends out a report. You could, for example, tell it to check http://www.yourwebsite.com/stolen.htm and if that URL is valid then a report is sent. Alternately you can set Prey to fire off a report to your email every time it runs. You'll need an email address and the SMTP information for your email server to set up Prey. The Linux and Mac versions have already been translated into English but the Windows version is still awaiting translation. It was easy enough to set up despite the non-English interface. Prey is open source and available for Windows, Mac, and Linux.