[techcor]

Must be lunch, suddenly everyone's posting. Shouldn't have whined about not getting any.

gas-core nuclear propulsion

Excellent! That's the sort of thing I wanted to see in the replies. Any more info on those? As for the "Greens"... they are exactly why I'm trying to tie in the power from nuclear waste part.

[Brett66]

Here's some links on Gas Core Nuclear Rockets:

Astrodigital.org

Here's one of my personal favorites, Project Orion:

Project Orion: Its Life, Death, and Possible Rebirth

Here was a real contender for Mars propulsion Sytem, until NASA cut funding for it last year:

VASIMR: The Plasma Rocket

Basically, everytime scientists say "here, we figured it out! We can get you to Mars in three months or less"
NASA says "thanks, but we really weren't serious"

[Brett66]

If they could develop a small reactor that puts out a lot of power using Americium, it could be used to power a VASIMR drive. The VASIMR can reach an Isp of 30,000. That's up there with inertial fusion propulsion. I don't know if it would be better for direct propulsion or as a power source, but either way we could accomplish remarkable things in space travel if we had the will to do it.