In the April issue of Chemistry World magazine I wrote about how the Bill & Melinda Gates Foundation wants to improve sanitation in the developing world: by invoking the dark arts of odour masking and the science of something called olfactory white noise – a topic that’s equal parts chemistry, physics and kidology. And the small matter of life or death.

Other clever tech I’ve covered lately elsewhere: Green light helps mitigate feelings of pain, but only if you actually see it visually and it enters via the eye; so what’s going on there?