  We report on a very simple and inexpensive method for determining the speed
of an electrical wave in a transmission line. The method consists of analyzing
the roundtrip time for ethernet packets between two computers. It involves
minimal construction, straightforward mathematics and displays the usefulness
of stochastic resonance in signal recovery. Using basic electrical properties
of category-five cable students may use their measurements to determine the
speed of light in the vacuum to within a few percent.
