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A sort of wiggly shape, made using TopMod. It was originally going to be hollow (but the Rind Modelling tool only worked with unprintably thin walls) and smoother (but the next level of Catmull-Clark remeshing had 550k faces)...but never mind.
(incidentally, 'infinitangle' is a portmanteau of 'infinity' and 'tangle'; obviously, none of the angles in the shape are infinite!)
Update: it's now been replaced by the version that isn't eight metres across. I hope.