Okay, this is just plain cool. Watching MacBreak 59 I came across the Pen-it from Hitachi Maxell. I suggest you watch the video (the segment starts about 6:35), but basically it's an ink pen with built-in Bluetooth. When you use it to write on special paper (which has been pre-printed with literally millions of little dots), it records your strokes for later wireless upload to your Mac. Apparently the pen has a tiny camera which makes this possible. The Pen-it NOTES application on the Mac then retrieves your scribbles as vector data(!) which can be saved or further edited on the Mac. Of course, as Merlin Mann notes, this locks you into their paper, and they don't say exactly how much it will cost. It is also not clear whether this is compatible with Apple's Inkwell technology.
Since this is a brand new product for the Mac (though a PC version has been available for a while), their website is rather incomplete. However, they are running a special promotion for Macworld with a $100-off coupon, bringing the price down to $199 for the pen (and USB charger), one notebook, and the software. It appears that this is the same technology (from Anoto) behind Logitech's io2 Digital Writing System, but it's not clear at all whether the Logitech pen (which is Windows only), would actually be compatible. (If it is, three 128 page notebooks of the Logitech pen's paper sells for about $12.)