How silly of us all to never realize that the butyl methyl sulfide molecule is not a liquid, but a motor. Thankfully, some clearheaded chemists at Tufts University were able to make us see this compound's true nature.
According to the BBC, by running an electric current through the molecule, the entire structure spins along its sulfur atom:
The butyl methyl sulphide molecule was placed on a clean copper surface, where its single sulphur atom acted as a pivot.
The tip of a scanning tunnelling microscope - a tiny pyramid with a point just an atom or two across - was used to funnel electrical charge into the motor, as well as to take images of the molecule as it spun.
It spins in both directions, at a rate as high as 120 revolutions per second.
But averaged over time, there is a net rotation in one direction.
As for uses—oh, yeah, there are actual uses for this thing!—scientists believe that this molecule could further be developed into a motor to power nano-sized devices in fields such as medicine. [BBC]