Probably not all doors should offer previews, all the time, but this is undeniably wonderful. As it is, the knob offers bi-directional viewing; I wonder if you could half-silver one side and make it one-way? Johnny Strategy at Spoon & Tomago writes:

In conjunction with Design Tide Tokyo, architect Hideyuki Nakayama Рa prot̩g̩ of Toyo Ito Рhas teamed up with UNION, a manufacturer of door handles and levers, to create a glass globe doorknob. As you approach the doorknob you catch a glimpse of what appears to be another world, waiting for you to enter and join, but in fact is a reflection of the room on the other side of the door.

[via Gizmodo]

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