The loser films a full, sincere cover of a league-chosen song, no autotune, no cuts, and posts it publicly. Song selection targets the loser's vocal range from a safe distance. Views are tracked in the league chat like a stock ticker.
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: fantasyfootballunlimited.com