A Ballbuster vise taken to the next level, upgraded with 12mm screw, 200+ spikes in total, 60mm X 60mm X 42mm height. For when you really, REALLY want to punish yourself or your subject!
Print each part separately lying down, even the screw handle. The body should be printed with the big openings upwards (like in the picture). Supports can be needed for the opening on the sides, I would recommend tree-support if you have it.