It's running Windows 2000 on a 166MHz CPU with 64MB RAM, 4GB hard disk, and a 7.1” screen. It also has 2 PC card slots, a small speaker, and mike and headphone jacks. Mine came with an external floppy drive and a docking station (which provided access to a VGA, a serial, a parallel, and a PS2 port). The screen is 7”, which should give you an idea of the general dimensions.
If you look at the photo you'll see a small circle to the right of the screen. It's a trackmouse. There are also a pair of mouse buttons on the backside for the screen. If you put your thumb on the trackmouse and grip the screen then the mouse buttons should be right under your fingers.
It is surprisingly zippy for such an old system. I'm not going to try to install anything new, but it's a little surprising how much WinXP software will work on such a limited CPU. So far I've installed Mobipocket Desktop, MSReader, and a few other basics. Lucky for me it came with a lot of the usual apps you'd expect to see on a laptop (Opera even), which saved me from having to go looking for them.
I got it because I didn't have a Win2k system nor did I have one of the old Librettos. I wanted to get it so I can use it as proof of how bloated modern OSes are. I've got a full desktop OS running on a 166MHz CPU and it's only slightly more out of date than WinXP. Can you imagine what would happen if I tried to run Win7 or Android on this? *snicker*