NASA tested their new Scramjet engine yesterday, achieving a speed of Mach 10, a new record for a jet engine. Here is a link to the CNN article.

http://www.cnn.com/2004/TECH/11/16/scramjet.delay/index.html

Also here is a link to an article describing the engine.

http://www.aviation-history.com/engines/ramjet.htm

I think this is very interesting, and has possibilities for reusable space vehichles, although that's a few years away.

Thats honken

I was thinking tonight about one other huge advantage. The absence of moving parts would make maintainence much easier.

Sure won't come cheap, but what does? How long to fly from Missouri to Afganistan in a scram jet powered bomber capable of delivering 80,000 lbs of ordinance as a B2-b does today? Scram jet speed + stealth technology & high capacity? How much to buy 500 of them, equipped with all the right toys?

Considering they hit mach 10 on their first test, I would guess the potential is that they can take it higher and faster. Even Mach 10 is 7000 mph (roughly). At that speed, a plane should be easily able to arrive anywhere in the world in four hours.
The other potential is to reach orbit using this technology. That could make space manufacturing and space tourism economically feasible. It may be expensive to develop, but much more costly in the long run not to develop it and watch someone else do it.