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Yes, your PC has lots of little capacitors.. but don't go looking at your moniter.. it has huge capacitors.. and i have inadvertently discharged a 40 volt capacitor.. (a lot bigger than a chicklet!).. and trust me, 40 volts is no fun.. monitor capacitors can be quite high voltage.. 200 to 1000 volts... not something you want to accidentally discharge.
and yes, mobile home still use gas powered refrigerators.
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Dear of troy: it is not just the voltage rating of a capacitor that matters. More importantly, the area that is charged determines the amount of energy that can be stored. This is measured in "farads", eponymic for Faraday, I suppose. Some of the early experimentors used Leyden jars, which were coated on the inside with silver plating, I think. Several of them in series could give an extremely unpleasant surprise if discharged from one hand to the other. Interesingly, there are eels that can store up a charge powerful enough to cause careless wader in tropics to be stunned and drowned. The muscles act like a long string of Leyden jars, and store enough electrons to cause an appreciable current. I think I have read of it being possible to make a light bulb flash with their discharge. I'll try to see if I can find anything on Internet.
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TEd
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Nope. A condenser has no moving parts. What would get ruined is the compressor.
To piggyback on what Bill explained, this is how an AC unit or regfrigerator works.
The cycle starts with a gas at room temperature. Simple physics here: any substance has a certain amount of energy in it, which can be measured as heat or temperature. A cubic foot of air at 75 F has a certain amount of heat in it. Now, if you compress that cubic foot of air to one tenth or one twentieth of that volume, all of the heat is still there. But it gets concentrated. Consequently the measured heat of the smaller volume of air goes up dramatically.
The gas we use in these machines becomes a liquid at a certain pressure. The liquid then goes through a series of cooling fins (look on the back of your refrigerator. Lots of long skinny tubes (which means a great ratio of surface area to volume. The hot liquid cools down to room temperature.
Then the cooled liquid goes into an expansion chamber, where it expands back to the original volume. But the heat that was there originally is gone. So the expanded volume is MUCH colder. The very cold gas is piped through another series of thin pipes where it sucks up the heat that is in and around the pipes. That's how the coils in your freezer and refrigerator get cold!
Then, the warmed-up gas goes back to the compressor where it is compressed again and condenses into a liquid in the condenser.
You have just pumped the heat from the refrigerator into the air behind it. That's why you have to make sure there is good air circulation behind your refrigerator and that those external pipes (coils) are free of dust. The heat has to be able to go somewhere.
TEd
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One little caveat, TEd. When you compress gas, you do work on it, and that takes the form of heat.A simple demonstration of this is to take a bicycle pump, put your finger over the place where the compressed air comes out, and push the plunger in -like a porcupine making love- very cautiously. If you press the finger over the opening too tightly, and move the plunger too powerfully, you can get a painful blister.
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I suppose that the engineer said that I would ruin my compressor--and I've simply mixed the words up over the years...Yes, those verbal tics do tend to accumulate over time, don't they? 
The idiot also known as Capfka ...
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Volta, Alessandro, Count (1745-1827), Italian physicist, known for his pioneering work in electricity. Volta was born in Como and educated in the public schools there. In 1774 he became professor of physics at the Royal School in Como, and in the following year he devised the electrophorus, an instrument that produced charges of static electricity. In 1776-77 he applied himself to chemistry, studying atmospheric electricity and devising experiments such as the ignition of gases by an electric spark in a closed vessel. In 1779 he became professor of physics at the University of Pavia, a chair he occupied for 25 years. By 1800 he had developed the so-called voltaic pile, a forerunner of the electric battery, which produced a steady stream of electricity (see Battery). In honor of his work in the field of electricity, Napoleon made him a count in 1801. The electrical unit known as the volt was named in his honor. See Also Electricity: History.
I remember reading somewhere that he had dissected some frogs legs, and hung the muscles in a way that they came in contact with metal, and twitched. The fundamental fact is that when any two different metals are suspended in water, a weak electric current is produced as one of them goes into solution. This is called electrolysis, and is the reason that aircraft rivets loosen slowly if rivet composition varies even a very small degree from that of skin. It is also the reason that touching a fork to a tooth filling may be disagreeable. Some combinations of metals produce enough current to be useful. Hence the Voltaic cell.
"Volta, Alessandro, Count," Microsoft(R) Encarta(R) 98 Encyclopedia. (c) 1993-1997 Microsoft Corporation. All rights reserved.
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Interesting that essentially all terms for electrical units are eponymous: volt, ampere, ohm, watt, farad, henry and joule. I am aware of only one exception: mho, derived from ohm. http://www.bartleby.com/61/charts/M0182500.html
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