The Acorn AKF20 monitor stand for the Acorn BBC A3000

Due to its single box design, Acorn produced a novel monitor stand for the Acorn BBC A3000 in an attempt to reduce the overall amount of desk space the computer and monitor required.

The stand was designed to slide onto the back of the A3000, resting on its shoulders providing a stable monitor platform through three points of contact. 

The stand is affectionately known as a "Bird of Prey" due to its vague resemblance to part of a Klingon Bird of Prey warship as featured in the Star Trek franchise.

You can see it setup with an original Acorn AKF12 monitor in the photo below.