Seagate has just announced that they’ve sold their 1 millionth Momentus XT hybrid solid-state/mechanical hard drive, an interesting development for the hard drive manufacturer especially considering the rise of expensive SSD drives. These hybrid drives run at 7,200 RPM, nearly twice as fast as standard mechanical drives. The drives contain some solid-state memory as well as a full mechanical drive and offer speed improvements at a very low initial cost.

The Hybrid drive is an interesting technological advancement. It’s cheaper than a full SSD drive but thanks to a 4GB cache you can read and write to the drive – at least in theory – nearly as fast as you can with a SSD drive.

To be clear, this isn’t a full SD drive. The speed savings are eventually reduced by the dependence on mechanical parts, but the price – about $99 for a 500GB model – is pretty good for a 7,200rpm drive.