Hate to be the voice of dissent, but I like 'em!! Granted, if I wanted something that small, I'd go for a Mini Cooper S over a SmartCar, but still, I love the concept of it.
I've actually driven something very very similar to this, even a little smaller. The top speed was 38.5mph going down hill with the wind behind. It was completely street legal but could only go on roads where the posted speed limit was 45 or less. It was actually kinda fun, I'd never use it as a "car" but taking it around the neighborhood or just down the street for some quick errands was really fun. Lots of questions about it too.