Sprinkle your hair with water for luck
When: 15th May every year
Where: Ancient Rome
Mercury was the Roman god of merchandise, commerce and gain. The Ides (or middle) of May was recognized as his birthday and it became a festival of traders and merchants.
The Roman merchants considered it good luck to sprinkle their merchandise, their ships and their hair with water from a fountain near the Caperna Gate using laurel boughs. They prayed to Mercury (who legend has it was a bit of a thief) for profit, and for the continued ability to cheat customers! There was then much dining and feasting together to seal the deal.