Just a sampling of the informative, literary art that abounds here: "The best way to clean pennies is by using the steel wire brush wheel which is included as a bonus on most table mounted grinders. Get a "Vice Grip" or similar type locking plier and use it to secure the dirty penny while you hold the pliers as the rotating steel wire brush wheel is scrubbing away on it. I found it only takes about 10 seconds per side of the penny to clean it to such a bright shine that it looks like gold!" http://www.pennycollector.com/cleaning.html
My favorite from lower down in the "Cons" section to using the wire brush wheel: "Somewhat abrasive to penny surface..."
On a side note, I wonder what would happen if you put a 1943 steel in one of those machines they have at zoos and amusement parks.
I've wanted to for a while now. I need to start carrying a steel on me at all times in case I see one if the machines. On one hand I want to get a unique object to show to friends, on the other it would be kinda funny if it messed up the machine...
Don't give me any ideas! Oh! I found bleach and a toothbrush (preferably not the one I'm currently using) does a pretty good job on them.
I thought this site was a joke put up by one of you guys. But apparently it's not. They forgot the cleaning technique of using dynamite. Very effective for stubborn, ugly toning.
Not a joke, but these are cleaning tips to be used on coins before running them through a press to make elongated cents out of them.