A themed karaoke session where every song the loser performs must contain 'lose', 'loser', or 'losing' in the title. Two hours minimum, from Beck to Beyoncé. The catalog is deeper and crueler than you'd expect.
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