MRAM stands for magnetoresistive random access memory. NEC recently announced that they've developed an SRAM compatible MRAM that can run at 250 MHz, which they claim is the fastest MRAM in the world. MRAM is swell because it's non-volatile: it remembers what you just told it even if you turn the power off. If it's as fast as SRAM there's no competition.
The unique MRAM was designed and fabricated by NEC and has a memory capacity of 1 megabit. Incorporating a memory cell with two transistors, one magnetic tunnel junction, and a newly-developed circuit scheme (3), the new design achieves an operation speed of 250MHz; double that of conventional MRAMs and almost equivalent to that of recent LSI-embedded SRAM. Tests carried out using an internal signal-monitoring circuit demonstrated data output time of 3.7 nanoseconds from a 250MHz clock edge.
MRAM are expected to generate new value and applications for future electronic devices thanks to their nonvolatility, unlimited write endurance, high speed operation, and ability to cut memory power dissipation in half. For example, these features could enable instant start up of PCs and prevent drive recorders from losing data after a sudden break in power in the future. As substitutes for system LSI-embedded SRAM, MRAM can provide even more value as they are expected to enable extremely low power dissipation of system LSIs because they can sleep when they are not in use and wake up instantly.
"Sleep when they are not in use and wake up instantly" sounds like the MIS guy at my last job.