You could use an RCX to control and power the train motors. Fun times from a simpler world, the downside was obviously that you could have only one train running on the grid because the power was supplied back to the rails!
I do like the version we have, as you can theoretically have an almost unlimited number of trains running. But yeah, it was really frustrating to have them cease production.
On the other hand, based on the photos in this article, it looks like the traction motor assembly may be common across recent generations which would allow tinkerers to make their own controllers.
