lightfield displays (true displays, not "hardcopy" holograms) require lots of processing for anything not pre-recorded, and still quite a bit for prerecorded stuff, due to the simple fact there is so much more information to be displayed at once


btw, i don't have a link at hand, but there is research being done on tactile feedback from virtual 3d environments in free air, somthing about focused ultrasound i think


and on a slightly more fictional note, it was Sony i think, they have a patent for a method of stimulating arbitrary neurons with transcranial focused ultrasound pulses, it's only on paper though, no experiments nor anything have been done