timothy from the now-you-can-charge-in-the-bathtub dept.
judgecorp writes "Steady progress on inductive wireless charging. There are now certified prototypes of chargers for Blackberry and iPhone devices that meet the Qi specification of the Wireless Power Consortium, which was announced last year. The spec has advanced from version 0.95 to 1.0, too."
We warn the reader in advance that the proof presented here depends on a
clever but highly unmotivated trick.
-- Howard Anton, "Elementary Linear Algebra"