Sweetshop owner Jose Martinez found the nickel piece while cashing up the day’s takings in Spain.
The head of Spanish King Juan Carlos has been morphed into the unmistakable profile of the world’s favourite cartoon slob.
The monarch’s visage with full head of curls has been skilfully crafted into the pop-eyed, big-nosed, bald-headed features of beer-swilling Homer, complete with his 5 o’clock shadow.
“The coin must have been done by a professional,” Mr Martinez said from the Asturian town of Aviles, northern Spain.
“It’s an impressive piece of work.” He said he spotted the handiwork after first discovering three euro coins from Malta.
The mystery defacer had not taken his scalpel to the other side of the coin, which displays the map of Europe.
But the high quality of workmanship has prompted speculation that other unusual euros might be in circulation.
Some have even suggested that the illegal work might be part of a republican conspiracy against the Spanish monarchy.
Meanwhile, Mr Martinez said neighbours and friends had offered him ?20 (?16) for the piece.
As news of the find rippled around the globe thousands more bids started to emerge from the Netherlands, Japan, Canada and the US.
But the shopkeeper maintained he was keeping the coin for himself.
Spot The Difference: Homer’s Head On Euro ! Dod