Via this brilliant geeklist, I found a downloadable "Rails" game. Similar to, but not quite, Eurorails, etc.
Well, since I've always consider Eurorails a multi-player solitaire game, I figured I'd give it a shot. The computer opponents seem reasonable (I got crushed in a four player game, and barely won a two player game). And they play fast, about ten seconds for one of their turns. Given the free-form nature of the game ("What shall I build this turn among my zillion options?"), I'm quite impressed. The graphics are nice (if a touch cramped). You have to read the manual, but it only takes a few minutes to get going. (The manual is a 7 page word document).
But it still takes 45 minutes as a two player game, and longer as you add computer opponents. (Given that games run 70-80 turns, that's another 10 minutes per opponent). Just another reminder why I never play those games. A computer slash the duration by a factor of 8 and it still takes too long! Amazing. But I may play it on plane trips.