Air travel and freight has become a staple of modern life, but it unfortunately uses enormous amounts of energy compared to ground vehicles because of the energy required to lift passengers & cargo and move at very high speeds. (If you like playing with eco-footprint calculators, just look at what air travel does to your score!) But an old technology--the airship, or "blimp"--allows air transport with energy consumption only slightly higher than ground travel. Speeds are much lower, but so is the cost, thus potentially filling a large gap in the current market.
The airship industry basically died with the Hindenburg, not only because of safety problems but because of the inconvenience of blimps requiring huge fields with tether-towers to land. However, these problems have been solved--modern steering technologies can eliminate the necessity for landing towers, modern material technologies don't require insanely-flammable coatings to prevent gas leakage, multi-chamber designs are more fail-safe, and today helium is economical enough to replace hydrogen. Airships are in fact much safer than jets, because their buoyancy and slow speed makes them fall slowly, and their smaller fuel requirements provide less explosive material on board. Several companies in the US and abroad are trying to expand the role of airships from the advertising ghetto they currently occupy, to replace some jet-based freight and transport; these companies include World Skycat, Ohio Airships, Global Skyships, and ATG Airships.
Don't hold your breath for this revolution--Victor Papanek thought it would happen twenty years ago, and it still hasn't--but keep an eye out for the re-emergence of this technology. And imagine the grace of taking an airship ride compared to a jet...
The thought of taking a leisurely trip in an airship is really appealing. I imagine it would be a lot quieter than a jet, too.
The price of helium is low enough for airships only because there are so few airships. If you want a reasonable number of airships flying around, the price will skyrocket.
Fortunately, the engineering problems in dealing with hydrogen are simple, and for the most part, already solved. Unfortunately, the publicity problems may well be unsolvable.
I'd love to travel by airship.
JP Aerospace is working on an airship that will take you to space - possibly to orbit:
Interesting stuff going on...