How about securing your Windows using your face ? 
You must have already come across Finger printing logins which have been included in many Notebooks as secure login feature. So how about facial recognition login?
Check out banana Security
All you need is the software and a webcam. BananaScreen is fun and easy solution to lock and unlock your computer using only your face. It locks when you move away from it, and, when you return, BananaScreen unlocks the PC in less time than it would take you to enter a password.
With a simple webcam, facial features are captured to build a statistical representation of the face. No picture is stored on your harddrive (or anywhere else) but only your face model (binary format).You have to create your face model first to use it. At present supports XP and 2000. May or may not work with Vista. Its still under beta.
So those having webcam can try it out.