Plenty of words have more than one meaning (I believe 'set' has most of all, so it sets a record) but one that's always puzzled me is cabinet. As the OED tells us, it's "a case or cupboard... for storing or displaying articles" and it's an "inner circle of ministers controlling government policy".
And today I finally learned the link between them, thanks to a furniture expert on The Antiques Roadshow. It seems that in the 18th century a gentleman would keep his fave trinkets in a cabinet to be displayed only to his inner circle of friends. They became known as 'cabinet friends' and from there it's only a short jump to a cabinet of the Prime Minister's closest associates.
English really is an unending source of small pleasures, don't you think?