According to this MIT Technology Review article, researchers at the University of Washington have developed prototype devices that communicate using just ambient radio waves — no batteries needed. The devices achieve this trick by varying how much they reflect and absorb radio waves, and scavenge power from those same radio waves. Bandwidth is low — only about 1 kilobit per second — and range is currently less than 1 meter, though that can reportedly be extended to about 6 meters easily. By eliminating batteries, such devices can become significantly smaller and cheaper, and could appear in a wide variety of scenarios, from contactless payments to warehouse item tracking, plus the killer app of locating your glasses and keys. follow link
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Move a File in the Finder
Sometimes you want to move a file in the Finder across volumes, not copy that file. Holding down the Command key while dragging ensures that the item is copied, and then its original deleted, adding up to a move.
- ExtraBITS for 19 August 2013 (19 Aug 13)
Researchers Demo Devices Powered by TV Signals