I'm still wondering how this works. It's a device that plugs into your USB port, and can be used in three different modes: Mouse, Note, and Tablet.
I guess I'm wondering if it's really completely wireless or whatnot. If so, does it just use some sort of location positioning system to determine where the pen is?
Neither the article I'm about to translate nor the official product page go into explaining how the thing works, but apparently it does.
Regardless, it's still badass. Those of you who have used tablets before should understand that there's some people who like to see how their hand is moving (me for example, this is the biggest problem I had with using a tablet.) Being able to actually write on a piece of paper, as you can with this product, is a MAJOR improvement in pen based input devices, IMO.
More details and pictures inside.
Mikimoto will release the PC-use pen-shaped input device, the "NAVInote" on March 1st. The price is 17,800 yen.

The set includes the "NAVInote Pen" which has left and right buttons matching those functions on a mouse, and also the USB-connecting "NAVInote Station."
Paper or a notebook is attached underneath the NAVInote Station (connected to the PC), and when the NAVInote Pen is moved on the paper, the display is linked to the pen. At the end of the pen is a ballpoint pen, meaning that the lines will also be written on the paper.
There is "Mouse Mode" which can be used just like a mouse, and "Note Mode" which can record pen movement data just like writing paper, and "Tablet Mode" which will match users movements on the screen 1:1 for the movements of the pen. The input area is, for Mouse Mode A3 horizontal, Note Mode A4 vertical, and Tablet Mode A5 vertical. The Tablet Mode input area is also user definable.

When using the included software, "HandWritingNavigator," users can write characters on top of image files, and send their written characters via Outlook as images in email.
The reading resolution on the pen is 0.02 millimeters. It operates on a button size LR41 battery. The size is 142 x 15 x 35 (H x W x D). The station operates on USB power, and is 170 x 54 x 35 (W x D x H), and weighs 60 grams.
Supported operating systems are Windows 98, ME, 2000, and XP.

Inspired by:
http://www.itmedia.co.jp/pcupdate/articles/0402/23/news061.html [1]
Product Information:
http://www.mikimoto-japan.com/beans/navisis_dm/navisis.htm [2]