A recent MIT LabCast features what they call Urban Pixels where public space lighting can be programmed in all kinds of ways. For example, instead of having the typical urban skyline illuminated by a static set of office building lights, the lighting display could be programmed so that it could be dynamic and active. William Mitchell sees it as liberating pixels from their traditionally confining frames.
Besides doing fun things with aesthetics, these urban pixels also have the potential to be environmentally friendly: charge during the day and then use that charge to power the evening light show.
Fun stuff. Definitely worth watching.