PB Stanford

An open source voting tool. It allows several different ways of voting, including ‘knapsack’ voting, where you split the fund between different projects to vote. They don’t offer any support, so it’s something you can use if you have the skills to set it up and host it.

Open source, though would need setting up and hosting

You can see a list of US cities who have used the platform through the link on their homepage: https://pbstanford.org/