City cars like the Toyota iQ and Daimler's Smart ForTwo have been gaining in popularity lately, with more companies looking to offer similarly-sized cars. Now Toyota's getting ready to take the next step, with an iQ-platform based roadster possibly coming to the Tokyo Motor Show in 2009 as a new design study.

A production version of an iQ Spider, or whatever it will be called, is not yet planned, but Daimler does offer topless variants of the Smart ForTWo, so it's at least possible. On the other hand, the iQ is intended to be a true roadster, not just a removable-top city car, so it's anyone's guess. The final determinant will likely be whether Toyota's research finds a market for such a vehicle.

Perhaps as cities grow more dense, fuel prices climb higher and emissions laws become tighter, even weekend getaway cars will have to be smaller and more efficient. On the other hand, the success of the Prius hybrid has shown how much vehicles with the right image can become fashion accessories, and a roadster could serve that purpose all the better, letting people see and be seen at the wheel of the efficient little car.

With power expected to come in the form of the same 1.0L and 1.3L petrol engines as the iQ hatchback, according to Auto Motor & Sport, it's sure to be efficient, and it could just be attractive enough to fill the role of trend setter. On the other hand, we'll just have to wait until late October, 2009, for the Tokyo Motor Show to know for sure.