Because history has proven that hard drives must get smaller and more capacious, Verbatim went and released the 500GB 2.5-inch SmartDisk HDD. Despite claims from others, Verbatim says this marks the first available 9.5mm Z-height 2.5-inch hard disk. The drive is made up of three 166GB platters striped with Perpendicular Magnetic Recording at 5400RPM. With enclosure, it weighs in at less than 6 ounces and measures 3.38-inches by 5.38-inches by 0.63-inches in both USB and USB / FireWire combo versions. Expect it this summer for under $300.
http://www.engadget.com/2008/04/29/verbatims-new-smartdisk-hdd-is-so-small-we-could-just-eat-it-up/