I would love to have an e-ink whiteboard type thing that I could just leave up all the time without worrying about power consumption. I'd say maybe the top third would be for calendar events/digital todo lists that sync automatically, and the bottom 2/3 would be a writing surface that would capture and sync its contents as well. It'd be amazing. I have a 10" Android tablet with Wacom digitizer which I do use a lot for brainstorming so that I have everything digitized, but I'd really like a bigger surface that I can leave on all the time.