Without a Trace

Did you hear the joke about the paperless office? Now that we've laid that myth to rest, scientist Paul Smith at Xerox Research Centre of Canada has made a real breakthrough with Erasable Paper. The paper is embedded with a material that changes color when exposed to light and is projected onto it by an inkless printer. The text disappears in 24 hours, so you can reuse the sheet.
Available Prototype
xerox.com/innovation/exp_paper.shtml