Planet Hunters 1 (PH1 b) is the first planet discovered by citizen scientists via the Planet Hunters project. Volunteers Robert Gagliano and Kian Jek spotted the signature of the planet in Kepler data as it orbited two stars in the Kepler-64 quadruple star system. It is found in the constellation Cygnus at a distance of around 5,000 lightyears from us here on Earth and is similar in size to Neptune, with a mass somewhere between 20 and 55 times that of the Earth, and 6 times larger in size. It take 138.5 days to orbit the binary star. It is one of very few planets known to exist in a circumbinary orbit and was the first planet found in a quadruple star system. You can read more about PH1 in the discovery paper here

You could also discover a new planet by taking part in the Planet Hunters project here