You also might want to check out Open Collective:
They are trying to re-imagine what's known as the "fiscal sponsor" relationship that has often existed between an incorporated entity (often non-profit) and unincorporated associations working loosely without the burden of incorporation.
The platform is agnostic and allows anyone in the world to connect a bank account to the platform via Stripe Payments (acting as "host"), and offer slices of that bank account to "collectives". These collectives can then transparently accept donations or payments through their collective webpage, and pay expenses requested by contributors. The platform mediates the inflows and out-flows. It can also act as just a transparent public ledger, in case people want to pass funds outside their platform, and just use the platform to manually communicate financial flows.
The platform has seen a lot of success in open source communities. In fact, the project founders have separately incorporated a national charity whose mission is to support community development, and another nonprofit whose purpose is to support open source software development. These both act as fiscal sponsor for hundreds of collectives worldwide, some of whom have budgets up to $500,000. They in a way scaling up the fiscal sponsorship model, and bringing down the admin burden through a platform they're building. These collectives can have many paid contractors, and yet none of the project leaders has had to go through the trouble of incorporating and managing a corporation.
It's quite the experiment, and they're definitely breaking new ground. In some jurisdictions, this is called a Shared Platform model, but they are definitely taking it to the extreme :)