U.S. pennies currently cost 1.83 cents to mint. Last year, the U.S. lost $55,000,000 in profitability due to the manufacture cost of pennies. The solution is simple and obvious: We should stop making pennies. They are virtually worthless, and there are more than enough in circulation already. But Americans have a pathological attachment to pennies and anything with the face of Lincoln, so getting rid of them is not a popular idea. So here's an idea I had. If we're going to keep making them, we should waste less material.
I suppose you could also interpret the hollow silhouette of Lincoln as a symbolic representation of the loss of traditional something something art.
It doesn't look very nice because I threw it together in about an hour, based on an image from Wikipedia. There's also the issue of the portrait taking up the back as well, which requires a medal turn instead of a coin turn like every other American coin. Oh well. It's an idea.