I've done two 24 hour (one way) train journeys, they're fantastic. Paris to Lisbon (for honeymoon) changing trains to Iberian gauge at Irun/Hendaye. And Viedma to Bariloche with the desolation of the pampas and the stunning views as you approach the mountains. I've also done a 3 night 4 day ferry through the Chilean Fjords from Puerto Montt down to Puerto Natales (in order to go do the "W" in Torres del Paine). So much stunning scenery to look at (and a bar at night!).

Travelling in Argentina many people use coaches to go long distances between cities as air travel is so much more expensive. You can get a coach from Puerto Iguazu to Ushuaia if you've got a spare 60 odd hours. The coaches are surprisingly comfy with big reclining seats that are not far off being full beds. We mainly did 12-14h overnight trips between cities so we got some sleep and saved on a night's accommodation.

I did a 24 hour rail trip from Narvik, Norway to Gothenburg, Sweden. We changed trains in Boden, Sweden. It was ... long. The first few hours, over the mountains, was fantastic. Once we passed Kiruna it was forest. Lots and lots of forest. This was in summer, and there was overcast light almost the entire time. There was no feeling of progress during the journey.

Yeah, waking up at dawn on a coach in the middle of the Pampa is a great experience. The front seats on the upper floor have a stunning cockpit view. I've done it on the trip from Bariloche to Buenos Aires and from Buenos Aires to Tilcara, and it's well worth the sore legs you'll get for sitting all that time.

Try the Amritsar to New Dehli overnight. For the real experience, try second class, where my friend and I shared a small cubby with a family of five (all flights cancelled for weather, no first class left).

That'll make you appreciate the Shinkansen or ICE networks.

Ah yes, spent 3 days on a train in India. First night with nowhere to sleep due to double booking.

or TGV (puts on his French hat :o) ).

Basically, modern train technology (although old train technology can have its charms)

Last year I went from London to Shanghai by rail, taking two weeks. For the first stretch we were spending each day in a new capital; by the time we got to Moscow the best part of three days on a single train was just what we needed.

It was a lot of fun, although I actually found Japan (where we caught a ferry to from Shanghai) more interesting.

That sounds like an awesome trip. Definitely more interesting than the drab Amtrack trip from D.C. to Miami I took. No stops, lots of industrial and abandoned residential blocks (and sound walls) the entire trip.

This was of course before the internet was available and laptops were yet the expensive convenience of the industrious business man.

I played lots of card games though.

Key point: do it in Europe. Also, preferably not alone.

I made the mistake of taking Amtrak Seattle-SF and then a later trip SF-Denver. Outside of a few interesting vistas I wouldn't have seen from a car (Mountains in Colorado, more in the Sierra Nevada area, and a few bridges in WA and OR), it really wasn't worthwhile. This was back in the Sprint 1xRTT/EV-DO days, and I couldn't keep a connection (worse than on the roads), the trains were delayed by 4-8h, and the onboard service was pretty horrible. I wish they'd just let Amtrak die an honorable death, with metro transit services, some privatized services for Acela, and maybe some specialty trains run in cooperation with the freight carriers on other lines (if profitable), probably with less frequency.

In contrast I did the Eurail thing back in 1998-1999, and saw lots of France (literally picking random destinations a long distance away; I didn't have much money, so I had to sleep on the train, so long night trips were preferable), Austria, Hungary, Germany, and Scandinavia, and more.

Ha, I did the random-overnight-train-to-anywhere-so-I-can-sleep-for-free thing during my Eurail summer too. It's not a bad way to see things you wouldn't have picked otherwise.