I've been lucky to have access to a Zcorp 450 3d printer at work and have been doing some experimenting with lamps. This example, which is hanging over my desk, is another curtain panel based form that comes from looking at barnacles and garlic.
Also these guys, Freedom of Creation, who do great work with a related technology called Selective Laser Sintering.
The Zcorp machine builds up the geometry by depositing layers of gypsum based power and drawing successive "slices" of the form in 2d planes of glue. Here is a video of the printing interface, where you can inspect your geometry to make sure the elements are thick enough, connected, etc.
If the geometry isn't thick enough, it crumbles, so doing fine details can be problematic. This can be a problem for doing railings, or other architectural details. But with doubly curved elements, the material is surprisingly strong.