I would love to have a two screen eReader that would open like a physical book. It could have multiple modes of operation:

1. a page turn would change both displays like a physical book 2. a page turn would just shift one page over and bring up the next page 3. one page could be 'pinned' and page turning would just occur on the unpinned screen

I would also like to be able to create bookmark 'pairs' that would bring up two (not necessarily adjacent) pages of my choosing. I think this would make eReaders much more useful for technical books.