Interesting and semi-related: http://www.opticsinfobase.org/oe/abstract.cfm?id=140598 http://www.opticsinfobase.org/oe/abstract.cfm?id=140598 Essentially, solv

Interesting and semi-related: http://www.opticsinfobase.org/oe/abstract.cfm?id=140598 http://www.opticsinfobase.org/oe/abstract.cfm?id=140598 Essentially, solving the traveling salesman problem in quadratic time using photon interference -- however, since the photons scale up as N^N, the Schwarzschild radius of the effect means it's not observable in less than exponential time.