There's the yaris S hatchback, which an equivalent comparison to the smart is about $3000 more: $1200 for factory installed leather (at select dealers), wabaso sunroof $1000, sports packages, comfort packages, fog lamps, ect to match the smart, but then y'know, in my opinion, its still kinda a boring car.
there is a can-am spyder 3 wheel vehicle capable of holding groceries, and doesn't require a motorcycle license in some states.
around the beach area here, there are these little moped engine 3 and 4 wheel vehicles, where 2 can sit side by side, its very low to the ground and restricted to under 45 mph zones, looks very unsafe.
the mini cooper is still pretty small, but much more expensive.
too bad that they quit making the honda insight, had the same CC of the smart car but got 60-70 MPG, and for under 20 grand was a bargain.