[LockAndLol]

Don't call them donations. Look at what reddit did: people can "give gold" to people for comments that they think were great. All it does is add some icon to a comment and put the person in a "gold club".

In games, people will buy so many visual improvements that add nothing but glam to their character.

Discord does... something, I can't remember what exactly, with their "turbo" and IIRC it costs discord cents, but the user pays dollars.

People will pay for the dumbest things. Give them a reason to sign up, add some kind of paid interaction that changes something visual or makes a dumb sound, add some tier system with context relevant names, and people might really pay.

[giantrobot]

Back in the stone ages Slashdot gave subscribers a comment bonus and an indication the user was a subscriber. An icon in the forums or some small benefit for "subscribing" goes a long way to get people to fork over a few dollars for something.

[PeterisP]

Lichess is a good example - their "subscription" gives a cool Patron icon wherever your user name is listed (usually the icon is just a circle that's filled if you're online), and that's it.