you mean a radiothermal generator?

Sounds okay- half-life of ~90 years, 1kg of fuel = 1kW if it's a good efficient one.

Like you say, it would be less practical for main power generation. But a collection of them would be a good idea for powering the life-support systems, basic comms with earth and so on.

And a nice helium-3 fusion reactor providing most of the power. If that worked, how about a power-sat network that would take a very powerful microwave beam from the Moon's fusion power grid and bounce it around to receiver stations on the surface of the earth? Good green (cheap!) electrons for all! The ability to provide power to rocket propulsion systems from above them (lowering losses and almost removing fuel costs)!

Conveient power for some sort of _good_ orbital base (I'm thinking more the Enterprise E than the ISS- with the better space-lifter tech there'd be less constraints on size/shape/weight of components)

And an effective weapon against anyone who dares piss off the guy controlling the satellites :P

The vulture got caught in the Microwave beam, unfortunately :(