Does a concurrent office document collaboration service exist that does not rely on 3rd party servers?
By "collaboration" I mean changes made to a document are quickly visible to others that have the document open.
Office 365 and Google Docs have nice collaboration features, but they require use of their servers.
SubEthaEdit for Mac (formerly Hydra) may have been the first realtime collaborative editor, and is still around. It's serverless; each running instance can act as a server for any open docs.
Search for "collaborative editor" for other choices. You may need to be specific about what features and platforms you require.
