Mark Rober (previously at Neatorama) customized his car horn to make three different sounds for different purposes. One is a “courtesy honk” that doesn’t sound nearly as rude as a regular horn. Wait until you hear the others.
Listen beautiful relax classics on our Youtube channel.
(Rober shares how he did it, too, with lots of links at the YouTube page to the parts he used, and even a WAV file for the sound. -via reddit
Source: neatorama