Not Maxwell's Demon, but the closest physical approximation is probably the Hilsch Vortex tube: https://en.m.wikipedia.org/wiki/Vortex_tube https://en.m.wikipe

Not Maxwell's Demon, but the closest physical approximation is probably the Hilsch Vortex tube: https://en.m.wikipedia.org/wiki/Vortex_tube https://en.m.wikipedia.org/wiki/Vortex_tube Pretty cool. (Har har)