Kent State
page on switchable windows

Polytronics Polyvision
an lcd film sandwiched between glass, it goes from clear to opaque when electricity is applied. could be used for curved surfaces. goes for $90/sq. ft.

Research Frontiers
licenses the smart window technology

Sageglass
similar technology allows for controllable tinting

Schott
makes display glass that's as thin as it gets -- 0.03mm -- and can be bended into shapes.

Sycamore Glass

Thermoview Alter-Lite
tintable window for consumers