We've seen a lot of concept vehicles in recent years from  SMART MERCEDES' small-car brand, many of which were fanciful test beds for far-out ideas. The fourjoy is both similar yet different, in that it looks too radical to be a real car, but actually does preview a new 4-seat, 4-door production vehicle coming next year called the forfour. It will offer a new dual-clutch transmission and dispense with the balky single-clutch unit in the current   .SMART FORTWO