Picture this. Eventually this will exist, mark my words. Some sort of device that will be able to, roughly at first but eventually more precisely, tap electrically, perhaps wirelessly, into your brain and record your physical experience of the world- record and interpret the smells, touches, tastes, sights, and sounds, and correctly interpret them, to a point you could sit in some sort of room that could recreate the expereince- the sights, smells, sounds. Or else, even simpler actually, would be to simply reverse and feed those recorded signals back into your brain exactly as recorded, so you can lay motionless (or even sleeping) and experience an...experience, all over again- it would be like watching a home movie but instead, going back and EXPERIENCING that moment again, as if actually there. Now THAT is a way to relive your memories.