well, there's this one under development http://www.newscientist.com/article/dn17476-ion-engine-could-one-day-power-39day-trips-to-mars.html http://www.newscien

well, there's this one under development http://www.newscientist.com/article/dn17476-ion-engine-could-one-day-power-39day-trips-to-mars.html http://www.newscientist.com/article/dn17476-ion-engine-could... 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 :)