Another idea just crossed my mind
On our public island there is near the center a medieval platform with a cell under it... for bad subbies i heard
If a subbie has been bad or maybe as penalty for dying the subbie gets locked there for 20 mins and all players online may tribute items in a chest right in front of subbie.
And each item represents a specific penalty. Like iron may represent chastity, a candel stands for waxplay, a leash for bondage, a potion bladdercontrol and so on... the exciting part is, subbie sees everyone who makes a donation but doesn't know what each player contributes