Refer to http:/www.cs.arizona.edu/mmc/Program.html and <a href="http://www.cc.gatech.edu/fce/contexttoolkit">http://www.cc.gatech.edu/fce/contexttoolkit</a> for more information on these context services. [0006] A context service may receive context information from a variety of sources, including electronic calendars, location sensors, and other sensors such as badge readers and motion detectors.