Scion: The perfect city Prius?

The perfect small hybrid?

The Toyota Prius has been a big hit amongst those interested in hybrid cars.

Scion has been a big hit with the under 35 crowd - an age cohort very interested in global warming and Iraq.

So, why not offer a smaller Prius as a Scion? Toyota has already expressed the possibility of expanding the Prius line, and one such derivative is a smaller city-Prius. Wouldn't Scion make the perfect brand for such a vehicle?