Siberian technician Anatoly Konyenko once manufactured tools for microsurgery, but in his spare time he spent 7½ years crafting a pair of golden horseshoes for a flea. See those, as well as the Lord's Prayer inscribed on a single human hair, a grasshoper clutching a violin, and a camel caravan silhouetted in the eye of a needle. Weird but fascinating.
Miniature Museum
Prague