SCIENCE SOMETIMES advances not by design but by happenstance. Thirty years ago a graduate student in chemical engineering at the Massachusetts Institute of Technology (MIT) was describing a bottleneck in his work over drinks at a bar in Cambridge, Massachusetts. A Harvard student heard and suggested a solution using microchip manufacturing technology that his lab had recently developed. The casual exchange led to a collaboration under the guidance of Donald Ingber, a Harvard cell biologist, that eventually helped pioneer organ-chip technology—lab-grown models of human organs on tiny chips. Dr Ingber would go on to found a biotech firm in Boston that commercialised the technology.