I was amazed by US railways, I lost count of the number of 1000m long freight trains we saw on a drive from El Paso to San Diego last year. I can' being to imagine how much load they were pulling.

When I was in Santa Fe the railyard there is both a commuter railyard and a drinking/nightlife area. Their commuter train looks quite retro, and even has a big road runner painted on the side :-)

http://en.wikipedia.org/wiki/New_Mexico_Rail_Runner_Express

My favourite train is the one below, the Shinkansen 500. Oh, and its duck billed sibling the 700 :-)

http://en.wikipedia.org/wiki/500_Series_Shinkansen

http://en.wikipedia.org/wiki/700_Series_Shinkansen

For the train treat of a lifetime, I'd recommend getting a Japan rail pass and going there for a couple of weeks.