The VASIMR engine is supposed to be capable of cutting down the travel time quite a bit, though it would probably require a small nuclear fission reactor to power it... which I'm actually all for, as the ship that goes to Mars will likely be the first true space only vehicle.
http://en.wikipedia.org/wiki/Variabl...oplasma_Rocket
Plus, on a geekier level, the glow from this thing at full power looks like the engine glow from ships in Star Wars
