I've always loved the fact that ‘Mac’ being a synonym for raincoat came from chemist Charles Macintosh’s invention of a way to water-proof fabric and his ground-breaking, but sweaty coats.

There’s obviously the option here for making the 200-year etymology the story. Or the chemistry, naphtha is mentioned as a fraction within the GCSE chemistry syllabus, but I think the real hero here is the unintended consequences of Macintosh’s invention. Within two years his fabric was coating a light-weight boat that could be carried between river crossings on an expedition in the Canadian Arctic. 20-years later and another inventor had created an inflatable boat made of his material that could be worn as a waterproof cape when not inflated.

-Bill