Western Digital just introduced the Black², a combination of SSD and conventional hard disk in a single 2.5-inch enclosure. It's not SSHD, however, with SSD cache. This is a normal 120 SSD on top of a normal 1 TB hard disk. For laptops with room for only one disk, this could potentially be the holy grail of storage.

The Black² measures 9.5mm in height, quite impressive when you consider it contains a 7mm notebook hard disk with a 120 GB SSD on top of it.

What's also impressive is that both communicate via a single SATA600 port, which technically shouldn't be possible. Western Digital came up with a pretty clever work-around. When you first hook it up to your computer, initially you can only access the 120GB SSD. After installing Windows and the special drivers for this disk, it turns into a single 1,120 GB disk with two partitions: one for the 120GB (the SSD) and one for the 1TB conventional hard disk. The OS sees it as a single disk, so it's the Black² that creates the distinction.