As Technology Review's Physics arXiv blog reports, they've devised a means to modify a standard 802.15.4 wireless network (commonly used by home automation services like ZigBee) to actually "see" movement through walls, and with some degree of accuracy, no less.

ENGADGET: Researchers create Amazing X-Ray Wireless Network!

And in the current issue of Applied Physics Letters, a group led by Haroun Ahmed at the Hitachi Cambridge Laboratory in Britain reports another vital step, a single-electron transistor that, for the first time, amplifies its input signal (though only by a factor of 3.7, several hundred times more weakly than a conventional transistor does).

ECONOMIST: The transistor��s heir