Seagate has started shipping its first batch of hard drives incorporating NAND flash for cache memory. The 'Momentus' 5400 SATA laptop drives will be offered in 80, 120, and 160 GB sizes with 256 MB of Flash memory.
Here's a quote from an article on Wired:
Seagate says, the hybrid drives will chop average boot times by about a quarter (40 to 32 seconds) and nearly halve the power consumption of the drive, compared to non-hybrid spinning disks.
Hard drive makers have been mulling the concept of including solid state storage to supplement hard drives. Hybrid drives are quieter and less power consuming, but the high cost of flash memory is a problem.
Using flash cached hard drives makes sense for mobile computing needs. Seagate's decision to rope in a 256 MB of Flash memory reflects a middle path in terms of the cost consideration. Seagate officials commented that the new disks will be priced about 25% higher than normal disk drives of the same capacity.