A Google engineer has developed a solar-powered data display for Google calendar information to use as signage in Google’s offices outside of their conference rooms (to display meeting schedules). It uses an ultra lower-power Cholesteric LCD display which can operate on energy generated from indoor light. Aaron Spangler, the engineer, claims on the video that Google uses six reams of paper, in 2200 conference rooms, every single day. So, given that, and the people-power required to change and update the signs, this is a significant time and money saver. Besides the Cholesteric display, the unit uses a PIC-based MCU and a Xbee wireless module.
The Radish, an indoor-solar-powered data display