Almost 40 wine glasses of different sizes filled with water and a lot of practice has yielded “Hedwig’s Theme,” which is the most recognizable melody from the Harry Potter score, played entirely on water glasses.
Japanese Youtube user murayu74 has uploaded a video of himself playing the song by running his fingers along the rims of the glasses, which produces a specific tone. There’s no telling how long it took to figure out the right amount of water, size of glass, or order in which to play the glasses, but it looks like murayu74 does this with tons of different songs, as evidenced by the multitude of water glass covers on his Youtube page.
Of course, all of this could have been bypassed with the right spell. Where’s Dumbledore when you need him? Watch the video below.