The Boogie Board is a reflexive LCD tablet that can be written on with a stylus — essentially a high-tech replacement for traditional dry erase technology. This retails for $30-$50 (these are in short supply right now), and can be written on and erased 50,000 times or so before the non-replaceable battery fails.
There is no way to save screens, so you can’t export what you’ve written as an image to your computer — as with dry erase boards, you’re probably stuck with taking a shot with a digital camera to preserve anything worth preserving. The company that makes these is working on a version that will save the screens, however.
Still, even without that feature, this looks like pure awesome.