So, I just randomly found out that apparently South Korea as a country believes in “Fan death,” in which fans kill people due to … well, the specific explanation given apparently varies a lot. Hypothermia? Fans removing all the oxygen in the room? Regardless of how it happens, the core belief is that if you sit in a closed room (somehow it’s important that the room be closed) with an electric fan on for a long time (eg overnight) … this could cause you to die.
(straight dope) (wikipedia)

By ‘as a country,’ I mean that fan deaths are apparently reported by the media and accepted by doctors in South Korea, which puts it a leap beyond the typical urban legend. Makes for an interesting example of how strongly a media and culture can affect a person’s perception of the world …