Worked for 52 Years, Still Running: 1912 C-T 4WD Electric Truck
Personally I'm wondering whether or not the steam engine will ever make a comeback. There have been some attempts (e.g. a company called Enginion with their SteamCell) that didn't get sufficient funding despite promising results.<p>Modern steam engines do not require lubricants, are low emission and can use renewable energy sources.