I've been learning and playing with twitter, and am blown away by the possibilities. I want to see all the twitter server code open-sourced, so companies can run their own internal twitter services. Would be great for collaboration, and minimising wheel re-invention.
Say I'm starting work on some code to parse XML from a particular app into a database, I set a twitter message "writing python code to import app XML into MySQL". All the other developers are monitoring their XML feeds, and can come tell me that someone else has already written the code. When I need to write my summary at the end of the week for management, I can look back through my twitter history to remember what I was up to. Not only that, management can watch all the feeds to get an idea of what different people are currently working on at a very fine-grained level. It is up to the manager not to micro-manage at this point :)
Twitter has open-sourced its queue server, 'Starling', which is a step in the right direction. I don't expect it will be long before someone starts implementing the full server as an open-source project.
Twittervision is one of the coolest things I have seen in a while. Watch what people all over the world are doing and thinking, right now! Watch a continent go to sleep and another one wake up...super cool.