In Islam's golden age, they came up with a trust structure known as a waqf [1]. A waqf is "an inalienable charitable endowment under Islamic law, which typically involves donating a building, plot of land or other assets for Muslim religious or charitable purposes with no intention of reclaiming the assets."

Working to endow charitable trusts might be a smart move for open-source projects.

[1] https://en.wikipedia.org/wiki/Waqf