VASSAL is free and open source so I figure I should leave it up to anyone to adapt Legions of Steel for it. Hey, if they can put Steve Gibson style Dalecks and Imperial troops into it, I'm all for it.
If, and that is a big IF, LOS was going to be something like a first person shooter, then I would look to Rainbow Six or Ghost Recon. Apparently there is a group that calls themselves "NATO" who are programmers that mod these games, but I have not approached them. Second choice for an FPS would be CounterStrike.
As an RTS then I would look to something like Starcraft although I think the "Age of..." series is much more elegant but anachronistic in setting.
As discussed elsewhere, there are now talks of an iPad game. VASSAL will encounter some of the same problems with leadership and covering fire due to their interrupt nature.