Two years ago I made a throttle control from some old meccano and some other parts my dad had lying around. I connected it to the game-port. The only pro was that when I bought a laptop it didn't have a game-port so I couldn't use it anymore, until I bought a usb to gameport converter.

Here is a picture of the thing.

The most interesting part. The gears to connect lever and the pot

I added this pot because a game-port device must have at least two axis to work in windows.

My USB to game-port converter.