You're looking at the work of Nicholas Chen, a PhD student up at the University of Maryland. He's been working on the concept of cooperative single screen ereaders for a few years now. As you can see from the video, he's pulled off some rather interesting features.
He has 3 ereaders there, not one. They're designed to work together so you can send a document (or even a single page) from one screen to the next. They're not connected physically and the only things keeping the 2 units pictured above together are magnets.
The video is after the break.
Nate Hoffelder is the founder and editor of The Digital Reader:
"I've been into reading ebooks since forever, but I only got my first ereader in July 2007. Everything quickly spiraled out of control from there. Before I started this blog in January 2010 I covered ebooks, ebook readers, and digital publishing for about 2 years as a part of MobileRead Forums. It's a great community, and being a member is a joy. But I thought I could make something out of how I covered the news for MobileRead, so I started this blog."