Imagine a site that auto-bills your credit card every month. You can specify projects you want to support, or just support a portfolio of projects that someone else has devised.
If so, please fill out this quick survey. I'm curious if this idea has legs:
https://docs.google.com/forms/d/e/1FAIpQLSfXIqUqsfDoUplWeWYs...
e.g. for one random example: https://www.patreon.com/monkey2
Obviously, there are also lots of open source people earning income from Patreon and the traditional bountysource too - but salt is the Bountysource clone of Patreon, specifically for OSS.
The Open Collective project mentioned in your sibling looks even nicer, but tops out at $5k/year.
These guys are making $24k per month on Patreon, for example: https://www.patreon.com/Kurzgesagt - I would guess it's just a function of their audience size and the amount of work they put into fundraising - actually asking people to contribute.
ElementaryOS have actually been working at this a little bit (unlike almost all other open source projects) - and they've built up to $1k a month on Patreon: https://www.patreon.com/elementary - plus ~$200 a month on salt/bountysource, plus direct donations, etc...
The problem of this model is that it's still basically B2C, a sort of charity for free work. What we need is enabling more B2B, i.e. a flow of invoices for some nominal "premium" work.