This is my take on a wall mount for the A1/P1/X1 build plate. It can hold 3 plates and is keyed so the plate cannot slide left or right once placed. It is held to the wall using command strips. In theory, it could just be mounted or sat on a desk but may not be very stable without modification.

Ignore the colored wall images, I used a sharpy and it bled. Didn't want to wait 5 hours to print in 2 colors.. ) ;)