Virtual trains... I guess

[clickmatch]

This is a japanese game where you can design your infrastructure. Looks interesting, though I suspect most people here want to hold them in their hands..

No direct link because my work blocks gaming stuff... but thethumbnails even look interesting. Check IGN and gametrailers, they are usually good.

http://www.google.com/search?q=A-Train+HX 

[arkansasrailfan]

There are many more simulators, like Microsoft Train Simulator, Trainz(how many diff.), and in Dec.08 mSTS 2.
Don't forget CadRail