OCZ is demoing the Z-Drive at CeBIT this year. The 1TB drive puts four 256GB MCL SSD's in a RAID-0 array and uses a PCIe X8 connection.
The drive has a total of 256MB of cache. The ASUS P6T motherboard they have it in is showing off 712MB/s for read operations and 500MB/s for write operations, all with nearly a zero access time. Once it hits the shelves you can except to drop about $1500 on the unit.