The most expensive Lincoln penny in history was a 1943 copper-alloy cent that was sold for $1.7 million in a 1996 auction. Nothing compared to this one, though. This penny is going be put on Mars for a nice $2.5 billion. Not bad!
Of course, those $2.5 billion are going to put a lot more stuff on Mars than just the penny. You know, like the best interplanetary robotic rover ever created by humankind.