In Lancaster, California, there's a musical road. When you drive over it, it plays the William Tell Overture. Unfortunately, it's out of tune. Here's why.
Thanks to David Simmons-Duffin, who figured this out about nine years ago: http://davidsd.org/2008/12/honda-needs-a-tune-up/
-- he seems to be the first to have figured out not just that it's wrong, but exactly what happened!