Microsoft and Samsung work on a Hard drive that uses flash memory as cache called Hybrid Hard Drive - HHD.
The idea is to combine the fast read and write times of NAND flash with the capacity of a hard drive. Apparently the HHD will be supported by Microsoft's next generation Windows called Longhorn for now.
More details on ElectronicsWeekly story. Via Gizmodo.
Apparently there is still no faster SATA hard-drive than the Western Digital Raptor SATA with 10,000rpm out there.