Holy shit, this is crazy awesome:
By using 3D printers as chemical synthesizers, researchers at the University of Glasgow predict they will be able to turn basic chemical constituents into personalized pharmaceutical drugs—and all on-demand. "It’s almost like a layer cake," said professor Lee Cronin. "You print the last reactionary agent first and then build other chemical layers above, finally adding a liquid at the top. The liquid goes to layer one making a new molecule which goes to the next layer creating another and so on until at the bottom you get your prescription drug out." Cronin’s findings have been published in the Nature Chemistry journal.