This is a bit off the beaten path of what we normally cover here, but this is just something that's too cool to not pass along.  Scientists in Israel have invented a way of making elaborate 3D models out of flat 2D discs.  It works by pretreating a special gel disc about half the size of a beer coaster with a special monomer solution that selectively shrinks when you heat it. 

It's being called "Chemical Origami"

While uses are limited at the moment, some scientists image that there could one day be something like a printer that prints a "metric" into a flat sheet, which you heat and it becomes a 3D object.  Not quite replication technology from Star Trek, but still pretty sci-fi all the same.