Whilst most BMW drivers are potential serial-killers, it cannot be denied that the Munich marque designs and manufacturers some rather impressive automobiles. It isn't their fault that most of their customers examine the boot-space before purchase to check that it will safely embrace the bodies of asphyxiated prostitutes.
Now comes evidence of BMW's social conscience: the turbosteamer. The thermal efficiency of the internal combustion engine in an automobile is appalling, at around 25%. (The thermal efficiency is the fraction of the heat energy generated in combustion which actually goes into mechanical work; the rest of the heat energy is carried away in the exhaust gases and the fluid cooling the engine). Transforming the efficiency of the internal combustion engine should be a priority for a society which seeks to mitigate global warming and to extend the lifetime of its oil reserves. In this respect, the turbosteamer is a significant step forward, increasing fuel consumption efficiency by 15%. (http://www.gizmag.co.uk/go/4936/). The turbosteamer uses heat energy from the exhuast gases and the cooling system to power a belt-drive attached to the crankshaft. BMW estimate it will take a decade to put this into production, but perhaps government should get involved in accelerating this timescale, passing legislation which requires new cars to have certain minimum levels of thermal efficiency, rising with each passing year.