Oddly enough, the tablet PC
has been around for many years. I have a smallish collection of them, and I use the lot to show my computer students
how PCs can take many forms.
I usually describe them as Palm Pilots on steroids. My IBM model 730T came stock with a version of Windows most folks don't even know exists - Windows for Pen. It is a version of Windows 3.1, tailored for use with a stylus as the input device. The Fujitsu Point and Stylus series can run Windows 9x.
These were originally designed for use by professionals who rely on clipboards and reams of paper - doctors, nurses, insurance agents, etc. All of the tablet PCs I have came from the insurance industry.
The IBM 730T had a 486 processor, PCMCIA hard drives,DRAM and a monochrome VGA LCD display. The Fujitsu Points have either monochrome or colour displays, and range from AMD 486DX4-100s to early low-power Pentiums, although these are rare.
They are still quite useful. I use mine as a display for radio direction-finding programs and for APRS.