A marvellous thing is the lobster:
Photo by Anna Langova
They have blue blood (based on copper, like Mr Spock's, rather than on iron like human blood), ten legs, a green liver, swim backwards, and, scientists are beginning to think, may be effectively immortal.
If you can't see a lobster in a river, sea, or on a plate near you, then a pop-eyed red-faced man is sometimes called a lobster (though not, if you've got any sense, to his face). A boiled lobster is an old rude name for a British soldier (because they wore red coats (some of them still do for special occasions)); a raw lobster was, by analogy, a rude name for a British policeman, who wear blue (though this, too, has fallen into disuse).
If you're in Eastern England, then a lobster, confusingly, may actually mean a stoat.
Lobster is also a word for jointed armour. The Lobsters were the name of Haselrig's famous regiment of Cuirassiers which fought on the Parliamentarian side in the English Civil War:
Painting by William Henry Charles Groome.
Other than that, there's a lobster in The Water Babies by Charles Kingsley:
And Lewis Carroll has given us a lobster quadrille:
Picture by Tenniel
And if you're really lucky you just might come across someone lobsterizing - that is, moving backwards.
Watch where you're going, now.
Spot the frippet: lobster. This word comes from the Old English loppestre, from loppe, spider.