Actually, a "long time" in space propulsion terms means more than a couple of minutes. The specific impulse of ion engines is sufficiently high that with sufficiently large engines, you would be talking weeks to get to Mars, rather than months by rocket.
which says a pound of thrust and Sun -> Jupiter (483 million mi) in 19 months and mars in 39 days (from earth i think). edge of the solar system is another 88.8 billion mi. that's a long time just to get out of the solar system.
i always imagined the USS Enterprise to be an interstellar ship. but it could work as a solar system taxi as well :)
