Smiling JOe said:
Your car probalby has a cruise control, but it can operate itself.
Sure you meant "can't"
Nach I was kidding about the cc ;-)
Think about it though, all of the 'lectronics are there - contact discriminating sonar and radar, GPS... Wouldn't take a whole lot of logic to stitch that together into a pretty robust command & control routine (though the "harbor" part would be way challenging compared to the "go out to some point and curise around" part.
Tech wise, that sort of stuff (not on land, of course, or in other crowded environment) is remarkably possible these days. Heck, a 'Nam vintage F-111 could, once airborne, fly to the target (and I believe effect a limited degree of evasive manuvers), drop ordinance, fly back and land all by itself (at least one documented instance of one of those pups landing with a deceased pilot). :!:
Pretty advanced tech for civy use... [bet that cost a bundle]. 
