I found an old webcam I had used years ago, underneath a lot of rubble in my storage room. I came up with this deadly idea of putting it to use - SURVEILLANCE.
Using this old webcam and a free software, I setup surveillance with image-capture-on-motion-detection for my cube at office as a first trial. Here are some sample captures from that trial. Mostly just people walking by my cube.
Next I'm thinking of leaving this on overnight - want to find out who does away with paper-napkins from my desk!
Going further, I see there are cheap "night-vision" webcams available in the market. And a friend of mine is thinking of building a real low-cost, low-power-consuming PC. Perhaps setup a custom-made, home surveillance system?