A reference-implementation of a web interface for an RSS-based, distributed Twitter clone.
Create a MySQL database and make note of its server domain name, username, password and database name. Upload the chirp_install.php file to your server, so it resides at the root of a domain or sub-domain. Run it, and it will download Chirp into a "chirp" subfolder and create a .htaccess file for you, then let you move on to setting up your database and a username & password for using Chirp. Run the chirp_install.php file again whenever you wish to update to the newest version of Chirp.
You MUST install this on one domain or sub-domain at root level (the domain name will be your user name). This is then equivalent to one "Twitter account" for one person, and will import statuses from other people whose RSS feeds you subscribe to ("follow").
To follow someone, use the Follow link on your server and type in their domain name (without the "http://"!) (It will then know to look for an RSS feed on that domain, at /.well-known/microblog.rss). After that, be sure to immediately click "Refresh Timeline" so you see new statuses from any accounts you follow.
To set up your own avatar icon, copy a square image into the "avatars" folder on your server, then you can select it in your profile. Currently there's no interface for uploading images.
What's this good for?
The idea is to lay down a simple, open exchange format for microblogs like App.net and Twitter, RSS, that can easily be load-balanced via Akamai or similar services. Everyone who can put an RSS file on a server can have a microblog. Everyone can follow them, whether they host it themselves or have one at Twitter.
For most users, their ISP or web hoster or one of the big services would host the feed, but it won't matter, because they're all interoperable. If Warner Bros. want to host Robert Downey Jr.'s statuses on their server, they can. If a user wants to use an iPhone client application to post, they can.
Since the user names are domain names, existing services can easily be integrated by using subdomains. E.g. @uliwitness could map to uliwitness.twitter.com.
To make this more likely, this code is under a very permissive license. Everyone can grab this code and just use it. Go ahead.
Copyright (c) 2012 by Uli Kusterer This software is provided 'as-is', without any express or implied warranty. In no event will the authors be held liable for any damages arising from the use of this software. Permission is granted to anyone to use this software for any purpose, including commercial applications, and to alter it and redistribute it freely, subject to the following restrictions: 1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required. 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software. 3. This notice may not be removed or altered from any source distribution.