A full mock funeral for the loser's season: casket (a shoebox with the roster printed inside), dress code, and a eulogy delivered by the loser mourning each player they mismanaged. League members offer condolences. Somber organ music is required by statute.
Budget note: this one costs nothing but dignity, which makes it a strong pick for leagues that would rather spend the pot on the champion than on the loser's downfall.
Seen in the wild: fantasypunishments.com