Depending on your requirements, CouchDB may be useful to you. I'm frankly a little bit leery about sticking my database straight on the Internet without somethi

Depending on your requirements, CouchDB may be useful to you. I'm frankly a little bit leery about sticking my database straight on the Internet without something in between to mediate access, but at least in principle CouchDB has a user authentication mechanism that you can you for your application. See also the somewhat passé http://couchapp.org/ http://couchapp.org/ (how quickly we tire of such things)