metadata for subsites?

I have subdomains that can be in several states, and some parts of the site should display differently depending on the state.

As an example, let’s say the site has moved from “in progress” to “completed”. A badge on the front page now says “Published”. Obviously I’d like to do more interesting things, but if I can do that I can figure the rest out. (Or ask specific questions later…)

It seems that if there is custom field/metadata capability for the sites, like there is for a specific page/post, that would be perfect.

Is there something like that?

I also considered adding the meta-data to the front page and then querying it from other places. Seems a bit clunky, but I can’t think why it wouldn’t work…

Is there a “right” or “better” way?