Since someone looking for help may find this post:
* Check all GFCI plugs (the ones with buttons in them in kitchens and bathrooms, usually one button is red). - what happened here.
* Check for GFCI or arc fault circuit breakers in the electrical panel (The breaker will have a 'test' button in addition to the usual lever switch)
* Check that the plug itself is well-secured. The wires can disconnect from a lose plug.
* Check lightswitches in the same room - That switch that "doesn't do anything" may actually turn off the outlet. Also, as switches fail they may only make contact when they are flipped. If it only works when the lightswitch is at an odd position, DO NOT try to get the switch to stick in that odd position. The switch needs to be replaced.
* Try another device in the same plug or the same device in a different plug - the light or appliance you were using may have failed.
* If your house was built approximately in the late 60's to 70's you may have aluminum wiring. That in and of itself isn't a huge problem, but a copper-wiring plug may have been installed on the aluminum wiring, resulting in the aluminum disconnecting from the plug. You'll need an electrician to fix this properly.
If you don't know what you're doing, DO NOT mess with any part of your electrical system that's behind a cover.
If you think you know what you're doing, DO NOT mess with any part of your electrical system that's behind a cover. Only open something up if you know exactly what you're doing - electrical parts have names like "Dead Man" for a reason.
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