The flags or VexiWiki is about flags and banners. It includes "encyclopedia articles about flags, flag designers (vexilogists), flag symbolism, flag specifications, and flag history" as well as pages for users to design their own flags.

Active wiki
This wiki is active. It has all the basics that a wiki needs. It has good content, but still has room to grow. Would you like to help?
It has the basics - core content, a significant number of pages, active contributors and at least one administrator. But it still has an area or two of significant weakness - too many stubs, uncategorized pages, only one active admin., etc.