The one interrupt no computer without a UPS can withstand: unplugging it. Sometimes the only way to recover from a bad crash. Refers to 110V, the standard mains voltage in North America. Does not necessarily imply turning a machine back on again afterwards.

Works well for most forms of electrical equipment which gets confused, for example VCRs which refuse to turn off timer mode.

The only problem is that often these machines have Non-Volatile Memory so it doesn't work unless you turn it off for a week. Ho hum...