Designer Kim Su Yeon has come up with a printer which, instead of leaving its mark, removes ink from printed Paper using laser technololgy. Pop in a page-full of martketing "insights" and out pops a white (and probably more insightful) piece of Paper. In such a way, Paper can be reused.
Whether or not this makes ecological sense depends on the process used to remove the ink and the energy consumption involved.
Via Yanko Design