This was initially demoed at FediCon 2025, but CrowdBucks is an open source, self-hostable fundraising system that allows people to financially support one another. You use your existing Fediverse account to hold a fundraiser, and can also donate to other people’s fundraisers as well. The form factor is kind of similar to Kickstarter or Patreon.
Support for other providers is coming. Bandwagon is in a similar situation. The overall goal is to support a multitude of options, so that no one payment solution has a monopoly.