Ask HN: What is the thing you've built that you regret the most?
I built a lighting system for <hotel chain you've heard of> to save energy by turning off hallway lights when not in use. The environmental aspect was great and saved hundreds of thousands in electricity. Someone eventually realized that the mesh network I built to connect all the lights together and report usage statistics could <i>also</i> be used to track employees moving throughout the building and catch them taking unauthorized breaks in the stairwell, so that's its main purpose now.<p>I'm a lot more paranoid about privacy these days.