Went somewhere today where they had a short film showing in a 4D cinema.
Was expecting it to be utter bollocks but the actual effect was amazing
Like 3D but as well as the glasses converting a mess on the screen to something other than a flat image there was also the appearance of stuff actually being out in the room and at one point there was a bubble that appeared to be floating in front of me close enough to touch. Bubble pops - a few drops of water are sprayed at you giving the impression that it was actually real.