Can it really be a donation to Whirlwind, or should those coins sit there forever? In case this person ever "remembers" or identifying info on his deposit or note, he would need to be able to claim it. I'm afraid also taking these coins as a donation anytime would set a bad precedent as well. Users might get scared to leave their coins in the mixer for long periods of time out of fear that they might be seen as "abandoned" and then taken by Whirlwind. I think any user deposit needs to never be touched or moved by Whirlwind without express permission from the user in a customer-service sort of scenario.