Elegant, easy, and effective, the thermometer is a tool often found in the ghost hunter's equipment box. Why? Drops in temperature aren't standard movie and book devices for nothing. One of the major signs of paranormal activity, according to time-tested theory, is a sudden onset of the cold.

The regular thermometers you use for bodily and room temperature can be used as your first hint at the presence of the paranormal. For a little more accuracy and speed, digital thermometers offer the instantaneous measurement to show drops in temperature. For even more pinpoint accuracy and carrying ability, many hunters use special gadgets known as infrared (IR) thermometers. These work without contact, measuring the temperature of any object by detecting infrared energy. These tools are extremely handy around the house, essential in many engineering and scientific applications, and useful in picking up the paranormal.

Many paranormal investigators will encourage the use of tools including thermometers, and use them in their own study, but they do caution a clear head. Read carefully about what temperature gauges can mean. Don't go overboard with money spend. And remember that tools should be a supplement to your own powers of observation and deduction.