Take the train from Zurich to Sargans (thefast one without stop) then a not too long bus-ride till Vaduz centre.Some museums and a cool view up to the Prince's castle :-) lots of souvenir, watch etc. shops, some restaurants.
I've driven it before. Not sure it's worth the effort. Better places to see for the distance I suspect. I was supposed to stay there a night but kept on going after stopping there for an hour.
