This guy detected an exoplanet with household equipment, some plywood, an Arduino, and a digital camera. Then made a video explaining how he did it and distributed it across the globe.
Exoplanets, or planets that orbit stars that are not the sun, are detectable by amateur astronomers, but it can take some serious, and expensive, equipment. Finding a way to track it with your camera and less than $200 of other equipment is pretty amazing. Check him his story in the video below.