Zero-power networking

Most interesting thing I ran into at the Silicon Valley Embedded Systems Conference:
Ramtron Corp, long-time pioneer in FRAM non-volatile memory technology, was demoing "wireless memory." This is a small (2kByte) FRAM chip designed to be read/written by RFID technology (distances up to about 30 feet.) It uses power derived from the RF transmission itself, and is "moderately fast" (up to 128kbps write speed)

One version has an auxiliary serial port that can generate interrupt signals when transactions occur. That sounds an awful lot like a zero-power radio receiver to me (compare to ~20mA for a zigbee receiver); server system writes data to FRAM, FRAM wakes cpu from deep sleep modes, cpu reads data from fram, writes response back (to fram) and goes back to sleep, server system polls fram after a suitable interval looking for a response... That could be pretty cool!

oops... http://www.ramtron.com/products/wireless-memory-rfid/gen2-uhf-ics-product.aspx?id=124