You have no reasonable expectation of privacy in public.
> * Someone sharing with another party in a situation with a large power imbalance (and so they refuse to sign an NDA with anyone)
Don't share it with them until they sign. If they sign and violate the NDA, you got your payday.
> * Someone sharing in a social situation where NDAs are not practical (romantic, familial, or personal relationships)
If you don't trust your spouse then get a prenup. The other categories aren't special.
That said, if your work is so easy to copy it probably wasn't (or shouldn't have been) valuable to begin with. Implementation matters more than ideas. So most of these concerns are silly to me.
You have no reasonable expectation of privacy in public.
> * Someone sharing with another party in a situation with a large power imbalance (and so they refuse to sign an NDA with anyone)
Don't share it with them until they sign. If they sign and violate the NDA, you got your payday.
> * Someone sharing in a social situation where NDAs are not practical (romantic, familial, or personal relationships)
If you don't trust your spouse then get a prenup. The other categories aren't special.
That said, if your work is so easy to copy it probably wasn't (or shouldn't have been) valuable to begin with. Implementation matters more than ideas. So most of these concerns are silly to me.