[biotinker]

There are more practical, everyday application for that fact as well.

When I lived next to a train track, I built a seismograph to detect oncoming trains, and had a white noise machine that would ramp up volume as the train approached to prevent the train from waking anyone up.

[doodlebugging]

That's pretty awesome. There probably is a market for this since I have seen several posts on city subreddits over the years where someone is asking why trains have to blow horns, why they are noisy, why didn't anyone tell them there was a track nearby, etc.

I think you could probably sell something like this. Good luck!