Thanks to work by BASF and Philips it’s now possible to turn a window into a light. When current is passed through this OLED panel light is emitted. When there is no current the film turns completely transparent.
To demonstrate the new material the two companies have installed them into a car’s sunroof. Although this probably isn’t the most obvious place to install a light it’s still pretty impressive. The concept is probably most suited to home sunroofs. Combined with transparent solar cells in theory they could power themselves, and therefor not only saving electricity (and the world) but making installation as easy as regular glass.