As a commented points out at Dan’s Data, if you combined this 3D scanner, made from Lego by Philippe “Philo” Hubain, with a 3D printer, also made from Lego, you could create infinte Lego given enough energy and print mix. Next: von Neumann Lego.
Extending the LEGO MINDSTORMS NXT to the Next Level [Philo Home via Dan's Data]



3d scanning from Surfdev, a specialist scanning service performed by a reverse engineering company.
Lego RepRap! http://reprap.org/
I welcome our brightly-coloured brick overlords…