Send the ISS somewhere.
The ISS, you see, is already an interplanetary spacecraft -- at least potentially. It's missing a drive system and a steerage module, but those are technicalities. Although it's ungainly in appearance, it's designed to be boosted periodically to a higher altitude by a shuttle, a Russian Soyuz or one of the upcoming new Constellation program Orion spacecraft. It could fairly easily be retrofitted for operations beyond low-Earth orbit. In principle, we could fly it almost anywhere within the inner solar system -- to any place where it could still receive enough solar power to keep all its systems running. nullnull
