Who's in the room?

People talk a lot about ‘presence' these days.  According to Wikipedia, "presence information is a status indicator that conveys ability and willingness of a potential communication partner - for example a user to communicate. A user's client provides presence information (presence state) via a network connection to a presence service, which is stored in what constitutes his personal availability record (called a presentity) and can be made available for distribution to other users (called watchers) to convey his availability for communication. Presence information has wide application in many communication services and is one of the innovations driving the popularity of instant messaging or recent implementations of voice over IP clients." Phew - not sure about ‘presentity'....

Loosely translated, it means you may not physically be in the room, but people can see whether or not you're available to chat, answer a question or provide advice.  

New on the presence scene is Twitter "a service for friends, family and co-workers.." (I think we call them colleagues here in the UK) "..to communicate and stay connected through the exchange of quick frequent answers to one simple question: What are you doing?" It's also been described as "the telegraph system of Web 2.0".

The instant messaging service that lets users send short text messages to anyone who cares to tune in, online or on their mobile phone.

If you want to keep track of friends, employees or children, or just want to join in conversations from contributors around the world, it's worth a look - it's gaining lots of fans and members and you can find out more here.