It's called the Boogie Board Sync 9.7 and it is really amazing! Not only does it save my writing, it also works as a digitizer when I plug it into computer with a micro USB cable. Now I basically can use this to take notes, but also use it as a miniature SmartBoard when hooked up to a projector.
Here's the link to the website http://www.myboogieboard.com/products/boogie-board-sync-9.html
I got mine on Amazon, but I'm sure they sell it elsewhere. I could totally see students using this instead of keeping loads of notebooks (and running out of paper) in their backpacks. The device syncs to Evernote so students could also sort their notes into different folder inside the app/program.
The device saves your drawings as a vector pdf and can be edited in a bunch of different programs. While the screen is not really contrasted too well, it does look great when sync (black and white when synced).
Here's a pic and I would love to hear what you think of it.