Buzz
Hundreds of people in southwestern Germany are complaining about a maddening buzzing noise. The noise only occurs at night, and does not seem to correlate to any known source of noise pollution, such as traffic noise or sounds made by electronic appliances.
The main page is here, but it’s in German, so use Babelfish to translate it.
I wonder if this could be linked with the Taos Hum heard in some spots around the world?