From the Columbia University E&HS newsletter, Safety Matters:

"A computer fire was recently avoided by a quick thinking employee and thorough investigation by staff. Upon entering the work area, the employee detected an unknown burning odor and immediately called Public Safety, who in turned called EH&S Fire Safety and Facilities to investigate the odor.  The investigation traced the odor back to a desktop computer tower that was emitting excessive heat."  Read the full article here: http://www.ehs.columbia.edu/News%20Letter/FA10Page5.html#pc