From David Pogue, NY Times: "...you gotta hate it when you plug in a flash drive to receive a file you need — and discover that the darned thing doesn’t have enough free space. That’s the beauty of Lexar’s Mercury flash drive, whose case has a “fuel gauge” — a bar graph that tells you, without even plugging the thing in, how full it is. Thanks to a technology called E-Ink, this graph is always on and stays visible indefinitely, without requiring any power whatsoever." (http://www.nytimes.com/2006/12/28/technology/28pogue.html)