The shunt regulators for high voltage in television sets (6BK4 comes to mind) were capable of producing X-rays under certain operating conditions. I wouldn't imagine that they'd be as powerful as say a medical X-ray unit, but it probably wouldn't be prudent to spend an extended amount of time near an open HV cage while troubleshooting.
See
http://www.time.com/time/magazine/ar...837185,00.html for one particular case involving GE sets.
-Jim