Things That Go Boom in the Night 
Article about the Moodus (Connecticut) noises and the findings of recent investigations that linked these noises with seismic activity.
http://www.gi.alaska.edu/ScienceForum/ASF8/896.htmlTaos Hum Page
Information and links about the "Taos Hum," a low throbbing sound heard in quiet locations worldwide, especially in the USA, UK, and northern Europe. It is not detectable by microphones or VLF antennae, and the source is still a mystery.
http://www.eskimo.com/~billb/hum/hum.html
Hum Haunts Indiana City; Its Source Is a Mystery
New York Times article about a mysterious low-frequency noise reported by residents of Kokomo, IN.
http://www.nytimes.com/2002/06/23/national/23KOKO.html
The Hum
Investigation into the cause and adverse health effects of the Bristol Hum, an obnoxious low-frequency noise heard in England. Conclusion is that the hum is due to a pulsed electrical signal.
http://homepages.tesco.net/~John.Dawes2/
The Moodus Noises
Account of the legends and modern accounts of the mysterious sounds heard in Moodus, Connecticut.
http://www.curbstone.org/index.cfm?webpage=96
Hum Forum
Yahoo Group for discussion of mysterious hums.
http://groups.yahoo.com/group/humforum/
Unexplained Sounds
About.com page gathers together information about mysterious booms, persistent hums, and underground rumblings that defy explanation. Includes audio clips.
http://paranormal.about.com/library/weekly/aa031599.htm
The Guns of Barisal and Anomalous Sound Propagation
Discussion of research into the physics behind mysterious sounds resembling cannon fire, heard at Barisal, India, and other locations around the world.
http://www.du.edu/~jcalvert/waves/barisal.htm
