Another good lifehacker post (especially for someone who just lost their laptop) is How to Set Up a Laptop Security System, ranging from physical security, monitoring, and retrieval. Good stuff!

There was a piece of software that I heard of or saw ages ago for (I believe) macs, which would capture a picture of you when you login or open the laptop and compare it to how it knows you look. If you look similar enough, no problem, if not, it would either ask for a password, start tracking, or something like that.

Anyone know what that was? Or was this just a dream?