Gnomes are famous for their festive springtime celebrations. Farm villages will often dye their hens eggs bright colors; with gnomish magic, the chicks that hatch from the eggs have the very same colors. The chickens eventually lose their hues, but the stronger the magic, the longer the color stays. In a gnomish village, one can easily spot the village shaman by his flock of gaily colored fowl.
Rich Romans raised fish in private pools at their villas. A favorite fish was lamprey, a parasitic fish which sucks off blood and flesh but made an excellent meal. A particuarly gruesome punishment for slaves was to be thrown into the lamprey pool, where their flesh was ripped from the bone by swarms of the jawless fish.
Medieval Britons didn't write contracts. Instead, men making agreements would clap their knives onto an altar and recite the agreement three times to seal a deal. Even after the Normans introduced written contracts, British nobles would wrap the parchment around a knife to authenticate it.
In a long-lost age, a party of adventurers are frozen into stone by the stare of some gorgon-like creature. An unscrupulous rogue, coming across the frozen party several centuries later, decides to haul off two of the statues to decorate his den. Upon his death, an artisan friend of his claims a statue and sells it to a rich merchant, passing it off as his own work. Years later, the merchant gilds the statue in bronze and re-sells it at a much higher price. After passing through the art markets for many decades, the statue ends up in the hallways of a mage academy. Imagine the chaos and confusion when a young mage's spell happens to break the curse of stone, returning the adventurer to life several centuries after his petrification! Is he interrogated by historians? Driven mad by the change of times? Or does he set off on a quest to find and liberate his other frozen party-members?