That's ok if you don't have a password on your account or you don't require a password to wake up from sleep. That's too dangerous so I recommend the following:
Set your Mac to use Filevault and go to Security section and select "Require password after waking up from sleep" so if someone opens up your laptop, they'll be greeted with a login screen. Now you want them to reboot...
What I did to make a 'honey pot' is this: I created a guest account (named it 'Krista') and that account doesn't require a password so if someone steals my laptop and reboots it, they'll be able to use this account. The account itself is locked down with very little permissions. I allow the use of a browser and the browser launches immediately after login (add it to Login items). The home page of the browser is set to my server's redirect page that uses meta refresh to immediately take the user to Yahoo. But I do get their IP. I also have curl set to ping a page every 20 min or so.
You could pay some cash for Orbicule (they use your iSight to grab pics of a person sitting in front of the screen) etc but this method is more than good enough. A step-up would be to proxy all of the requests from the browser through the proxy you control... but I haven't found a nice proxy to install on a shared server.
Unfortunately, I don't know of any method that would survive a reinstall of OS X but most thieves don't know how to do that anyway.