Twitter

Twitter can best be described as a cross between an IM client such as MSN Messenger, an RSS feed and SMS. Messages must be less than 140 characters and can include a link. The essential point is to answer the simple question ‘What are you doing?’ You can follow individuals’ messages or search on topics. At the time of writing, swine flu is getting a lot of play.

Digg.com

For some time now there has been an explosion in social media – MySpace and Facebook are well established and are in fact bigger than many countries in terms of membership.