This is Austrian designer Klemens Torggler demonstrating one of the kinetic sculpture doors he's created. It's pretty cool. And it is practical from a 'It doesn't swing into the room and take up any space' standpoint. But it's not very practical from a locking standpoint. I like a door that can lock. My apartment door is a bad example. It just has a hole where the knob used to be. When I go to bed at night I push a cinderblock against my side and hope for the best. *rustling, voices* Dammit, I'm on the shitter but it sounds like I'm being robbed right now.
Keep going for three worthwhile videos of different styles of his doors in action. I think you'll particularly like the second one.
Thanks to Icehawg, jules, Brax, Daniel and Scuttle, who prefer doors that are kick-downable.