2. The MacView, which is detailed here. A Polish guy apparently did it for a design project before the iPad was revealed. I'm sorry for using the word iPad.
3. Knowledge transfer (or mind melding, but considering the fact that two things on this list are from Star Trek already, I think it's best that you pretend I don't know what it's called)
4. A command/Z function (aka edit/undo) for real life scenarios. Actually, maybe a complete Photoshop toolbar for real life scenarios. For use only with discretion, of course.