I read an interesting article today about 2 different reverses on some of the 1992- 2000 Lincoln Memorial Penny. In 1992 the Philadelphia and Denver Mints used 2 distinct reverse types. One with the AM in AMERICA being close together and the FG (Frank Gasparro's) initials being far from the Memorial and the other version has a greater distance between the AM and the initials are closer to the Memorial. The closer AM is the rarer of the 1992-D cents. Heritage Auctions estimates that there is only 15 of the rare pennies that are currently known, but more may come to light. A MS69 Red Lincoln that was graded by PCGS sold for $14,100 at a Heritage auction on Feb 17 2014.
So before you give your little one that penny for the gum machine or throwing it in a penny tray at your local store, you may want to take a closer look. There might be a Lincoln in your hand that will bring a lot of cents into your pocket.