Around 11 years ago, I worked in a small 4-person office at a big tech company. We usually left personal items on our desks when we left for the day, assuming that they would be there when we came back the next morning. Over time we started to notice that small things were going missing. One of our co-workers always kept a few dollars in change a coffee cup on his desk that he would use in the vending machines. He asked us if we were dipping into it. Other things began to disappear as well, including a Kindle and digital camera.

We had no way to lock the doors, so I devised a clever solution. I set up an old ThinkPad in the corner of the room, and installed some free motion capture software on it that would upload anything it captured to Dropbox, and covered the light on the webcam with electrical tape. I monitored the folder for updates for about a week. On the first day, I realized what was happening. The late-night building security guard was poking around our desks, looking for things to swipe. In the clips that were captured, even with the low-quality resolution, it’s absolutely clear what’s going on. If you watch all the way to the end, you can even see the pièce de résistance, an iPod going directly into her pocket.

The video is also perfectly timed to one of my favorite songs. I’ve never shared this outside a small group of former co-workers, but I think enough time has passed.

Enjoy.