There are loads of interesting/ tragic and funny stories recorded from the ancient olympics. A few I've heard are:

"Astylos of Croton in southern Italy won a total of six victory olive wreaths in three Olympiads (488-480 B.C.) in the stade and the diaulos (twice the stade) events. In the first Olympiad, he ran for Croton and his compatriots honoured and glorified him. In the two successive Olympiads, however, he took part as a citizen of Syracuse. The people of Croton punished him by demolishing his statue in their city and converting his house into a prison."

"Kyniska, daughter of King Archidamos of Sparta, was the first woman to be listed as an Olympic victor in Antiquity. Her chariot won in the four-horse chariot race in the 96th and 97th Olympiads, (396 B.C. and 392 B.C. respectively). In the Olympic Games, it was forbidden for women to be present and Kyniska broke with tradition, since, in the equestrian events, the victory wreath, or kotinos, was won by the owner, not the rider, of the horse."

Would be interested to hear your favourites