Driving down the highway in South Korea can be a musical experience (just enough to get your attention, in case you're sleepy or not paying attention):
The road is carved into thousands of grooves. When the car tire hits the grooves, the vibrations turn into a sound source. It makes different tunes depending on the size of the grooves ... The rhythm is controlled by the lengh of the groove. For example to get one second of the "do" note, the groove is stretched 28 meters.
Link [ABC World News Webcast by Joo Hee Choo]