The Palm (palmOne) LifeDrive Mobile Manager was the first (and only) handheld to use an internal hard drive for data storage.
Tucked inside the LifeDrive is a Hitachi 4GB hard drive, the same type of drive that provides storage for some small drive-based MP3 Players released around the same time as the LifeDrive.
An internal hard drive allowed the LifeDrive not only to store large audio and video files, but also made the LifeDrive a viable portable storage device. The LifeDrive includes a file mode, like the Tungsten T5, allowing the unit to double as a mobile hard drive.
The LifeDrive is powered by a 416MHz XScale processor and has a 320x480 hi-res display. It also has both Wi-Fi and Bluetooth onboard.
Palm discontinued the LifeDrive some time ago, however there are still units for sale from limited retailers and, more importantly, eBay.