3D printed objects are usually rigid, or at least made of parts that were printed separately. This makes it time-consuming if not outright impossible to print large objects or ones that need to be flexible or adjustable.
The researchers behind Shape-It-Up call it a “Hand Gesture Based Creative Expression of 3D Shapes Using Intelligent Generalized Cylinders”, but it’s totally a pottery simulator. Decades from now, if – when? – Paramount Pictures decides to remake Ghost, the characters will be using Shape-It-Up while a dubstep remix of Unchained Melody plays in the background.