Seagate recently announced that it is shipping the highest capacity one inch hard drive available, with a capacity of 6 gigabytes.
The drive is projected to be able to store 150 hours of music, or about 3 000 songs at 128kbps. Expect a 6GB iPod mini and other hard drive based MP3 players soon. Other applications include PDA storage, portable entertainment devices, GPS devices and mobile phones.
The drive features anti-shock protection to ensure that music continues even when the device the drive is in is being subjected to movement.
More info here at Seagate.com