Okay, this is just stupid cool… Watch this CNC tube bender from Nissin. The bend geometry is translated into a set of instructions that control the position of the moveable die as the material slides out. There’s another (less grainy) video from a tradeshow. The formed tube is covered with grease because of the ridiculous amount of force and friction between the material and the die.
It really does look like it’s “pooping steel”.