Pennies and Trains

So, I saw the Lone Ranger in the theater yesterday to celebrate the USA's independence day.  I thoroughly enjoyed the movie, though the others in my group said it was not as good as they had hoped.  Oh, well.  But all the trains and train crashes got me thinking about pennies on railroad tracks.  Will a penny on the tracks derail a train?  What do smashed pennies look like?  Is it dangerous out there on the tracks? There is a good Snopes article about this practice.  In summary, no, the penny will not derail the train, but make sure you are well clear of the tracks long before the train comes rumbling down the tracks, so that the train doesn't flatten you, along with your penny.  Now I do not recommend engaging in any train-track-penny-flattening endeavors, though admittedly, flattening a penny won't change its value. It will still be as worthless as a normal one.
Another thing you can do with your pennies is use them to clean up the metal rails on your model electric train and car sets.  The gunk that builds up on the metal contacts easily comes off when you rub the flat side of your penny along them.  It will also keep the tracks nice and shiny without scratching everything up, like traditional cleaning items might do.