Would be very interesting to use bezier idea in a 3D modelling tool.. increasing polygons of existing objects in smooth way or making new object entirely with control points. Problem is it can become slow or complicated when interpolating neighbour triangles/polygons.

But something i did use the idea for is frame animation for 3D object. It looks better than "hard cornered" interpolation even though low frame count can result in model bending in unnatural ways.