I know OpenSats is a thing. I don't know if you would qualify that as a common good. They use a multisig to vote on where the funds go. No need for a smart contract though.
Discussion
I’m not familiar with OpenSats but it looks like they promote the funding of common goods.
nostr:npub1qny3tkh0acurzla8x3zy4nhrjz5zd8l9sy9jys09umwng00manysew95gx is a key member of opensats