Reflective Traffic Lights!
You may have noticed newer traffic signals being installed all over the United States, and Canada. These signals have a yellow or amber reflective border around them. This is such a simple design addition, but such a huge increase in visibility and safety. It was my idea too!
One night in 2002 there was a power outage which affected an area of King City township in York Region, Ontario, Canada. Standing on this very corner, I was deploying road flares with a York Region Police Department officer, as the traffic signals were out. The flares were being placed on each corner, and also at the middle lines of each road at the intersection. Even with all of these flares, the traffic was barely slowing down or treating the signal as a stop sign.
After observing the behavior, I was discussing the issue with the officer, and we were brainstorming a solution. I initially suggested that we could put red reflective lines around each traffic light, to remind people that they are there in the dark, and they should stop. But he said that red would not be a good color, so I said well, what about yellow? Since they are painted yellow anyhow, it wouldn't matter. We went over the idea, and eventually he liked it, and said he would submit it as a safety suggestion.
The rest is history. They began popping up around York Region in 2003ish, and now it appears that the idea is being put to use everywhere! It is an amazing feeling knowing my idea has gone nationwide. I know I can't really patent it, or make money off of it, which is fine, but it would be nice to be known as the guy that came up with the idea :)