Trains, trains and, erm, even more trains

Amazing Trains That Were Never Built
http://www.infrastructurist.com/2011/06/28/amazing-trains-that-were-never-built/

Prop-Driven ‘Rail Zeppelin’ Is Many Kinds of Awesome
http://www.wired.com/autopia/2011/03/schienenzeppelin/

Steam locomotives head from Bristol to Weymouth
http://www.bbc.co.uk/news/uk-england-bristol-13927817

There's even a Wikipedia article on transatlantic tunnels
http://en.wikipedia.org/wiki/Transatlantic_tunnel

And plenty of other websites on the same subject, like this one
http://www.popsci.com/scitech/article/2004-04/trans-atlantic-maglev

1960 monorail
http://blog.modernmechanix.com/2011/06/30/its-new-13/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+ModernMechanix+%28Modern+Mechanix%29