Redstone/Command Block Subway

I'm Starting a city build and I needed a subway. I wanted something a little more authentic than minecarts, so I've built a working subway, using Redstone, Command Blocks, and Pistons (for sound). When you enter the car in the station, there is a button at the front of the train, Press it to start the train. The train will keep running as long as you want. Press the same button to stop the train at the next station. Please feel free to use this in your builds. Of course give me some credit if you can. Oh ya and lots of DIAMONDS