Twitster is a PHP application for your webserver that allows you to do some cool hashtag or group following and then display it on any website/server that supports PHP.
I have a conference ID set up that we use each year to rebroadcast to everyone that follows it, but this is a new implementation idea to allow people to watch the stream instead of having to be part. You could even use this just for your own website or project:
# Publish your Twitter community on your own web site.
# Gather and publish tweets from the people and the topics you care about.
# Powering your site’s community with Twitter means little to no work for member participation. (Just tweet!)
The site has demos to watch and the install is a wizard. That is incredible as most of the tools like this would be a ton of code and steps with loose pages to work with.
To run this you must have PHP 4.x or higher and also MySQL 4.x or greater.