Have you ever had an idea, someone else made successful?

[Bulldog]

When I was 16, I thought of inventing a radio-controlled device that emergency personnel could use to change a traffic light they were approaching. My idea was that I'd sell it to municipalities with the catch that I got 12 of these devices for me and my friends to use legally. I don't know if this already existed before then and I didn't know about it, or if it was created later.

I have a couple others that I probably should patent, but I'm lazy.