Secret sliding bookcase conceals hidden door
This sliding secret bookcase door conceals a laundry room. It uses skateboard wheels, and could be used to hide any number of different entrances.
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The video is tilted sideways, but this secret bookcase door slides straight back into a small room. They use some type of hanger/slides at the top of the bookcase. This gives me some ideas.
Sliding bookcase door divider
Sliding bookcase passage
Sliding door bookcase - several deep
Sliding bookcase door conceal hidden passage from http://www.hiddenpassageway.com