This knot was created in Moment of Inspiration (MoI) from a script written by user bemfarmer based on work by Aaron Trautwein. IT HAS NO USEFUL PURPOSE - but it looks nice, and the shape would be a serious challenge for subtractive manufacturing. Note that this does require support and, I think, a raft. I found it pretty easy to print in PETG on a Prusa Original i3 Mk2 using Simplify 3D as the slicer. PETG is currently my favourite material. Looks good, stick well to the build plate and supports come away fairly easily. I printed the knot 'sitting down' and 'standing up'. Both shown in the photos. The 'standing up' variant took significantly less time and material.