Isn't it a federal crime to deface currency? Just asking. Scowl-Face says that Title 18, section 331 of the United States Code prohibits the fraudulent defacing, mutilation, alteration, or falsification of any U.S. coins, and this crime is punishable by fines and/or up to five years imprisonment (18 U.S.C. § 331). Unless somebody is attempting to defraud someone else by defacing U.S. coinage, it appears not to be a federal offense.
I'm fond of Abraham Lincoln, naturally (he loved cats, which all by itself makes him one of the greatest American presidents), but I really like so-called Indian Head pennies.
Because they're more expensive to mint than they're worth at face value, lots of folks want to abolish penny production in the U.S. That would be a shame, because folks in the over-50 crowd who remember how much you could buy with a penny in their youth want a visual point of reference. (According to my minions, way back in the day, you could purchase a cart full of groceries, a small automobile, and a round-trip train ticket to San Antonio for a penny. Frankly, I'm skeptical.)