hey fail

I kind of doubt it, the majority of what you need for other people to use a mod is also what you need to host. I'm thinking you could add a statement requiring a certain name of a server but that's a big maybe.
Well, here's a thought, you could go through and delete all the necessary code to host the mod, then release the mod with those parts chopped out and they wouldn't be necessary to play it. Hopefully a more experienced modder can answer your question more directly.