A 3-D printer, which has nothing to do with paper printers, creates an object by stacking one layer of material — typically plastic or metal — on top of another, much the same way a pastry chef makes baklava with sheets of phyllo dough.

The technology has been radically transformed from its origins as a tool used by manufacturers and designers to build prototypes.

These days it is giving rise to a string of never-before-possible businesses that are selling iPhone cases, lamps, doorknobs, jewelry, handbags, perfume bottles, clothing and architectural models. And while some wonder how successfully the technology will make the transition from manufacturing applications to producing consumer goods, its use is exploding.

A California start-up is even working on building houses. Its printer, which would fit on a tractor-trailer, would use patterns delivered by computer, squirt out layers of special concrete and build entire walls that could be connected to form the basis of a house.

The concept of 3D printing the objects you need - or that you think have a market - is amazing, no need to explain why. But I remember seeing a video of an inkjet printer (a normal one, not 3D) squirting chicken heart cells gel that, how shall I put that, kinda took the trouble to organize themselves into a chicken heart that started beating by itself. Take that, Frankenstein!

Story here and video here.