On a more serious note, folks should check out the all-new A400 from Airbus...4 engine t-prop, extremely efficient, capable of .70 mach, way up in the flightlevels (FL370 I believe). I'm not a huge airbus fan, but this seems like an uber-capable aircraft that burns a heckuva lot less fuel than a jet. Maybe we'll see these in our skies, or something similar, to offset fuel costs.

Seems like a sweet plane.

Airbus A400M Military Transport Aircraft – Air Military Transport at its Finest - Airbus A400M