Just when you thought it couldn't get any better - it does!
The low torque conundrum of the Stirling Engine is resolved with radioactive decay!
A bad idea on Earth, perhaps - see poster - but a brilliant development for outer space missions.
http://www.spacedaily.com/reports/Testing_Maintenance_Free_Engines_That_Power_Science_in_Deep_Space_999.html
https://www.federallabs.org/news/record-setting-power-reliability-and-efficiency-in-a-low-mass-free-piston-stirling-convertor
