Seagate has revealed a hard disk drive for laptops and netbooks that it reckons is the thinnest in the world. Called the Momentus Thin, the drive measures just 7mm in height, about 25% smaller than the porky 9.5mm of traditional 2.5-inch drives.

The skinny HDDs are available in 160GB and 250GB capacities, and feature an 8MB cache, SATA 3GBps interface and 5400rpm spin speed. They could allow the next generation of laptops and netbooks to be even thinner than existing ones.

The drive will be shipping in January to customers, and will no doubt be followed by similarly skinny copycat drives from Seagate's competitors. We'll keep you posted of further developments in the ultra-thin drive market.