Re: Sigh
Yes but according to Scientific American pneumatic tube transport over any great distance would require an enormous amount of energy.
"Nor should the tube be normal pressure either, like the pneumatic mail tubes of yesteryear, given that pushing all that air around would entail too much energy when expanded over hundreds of kilometers, not to mention an absurd amount of friction on the tube walls."
Unless you can build a completely leak proof tube, a partial vacuum tube seems like a bad idea. Any significant amount of air getting into a part of the tube could cause the pod the crash.
Regular Maglev is expensive because the clearance between the magnets and track is so small. Which means the track has to be almost perfectly flat, which is expensive to achieve. There is a bit of hope though as halbach array maglev has much greater clearances, and perhaps cheaper track.
The company SkyTran is pushing maglev pods as an intra-city PRT solution, but they actually look much better as a low cost inter-city train replacement (they can go fast on straights, but cannot go around tight corners). Japan's super expensive superconducting track maglev trains can already hit 600kph. I don't know if these pods could go anywhere near that fast though.
2 to 4 person pods would be much superior to trains as you could leave whenever you wanted.
http://www.skytran.com/maglev/