Twitter

Quick, quick, ahhhhhhhhhhhhhhhhhhhhhhhhhh!!!! Five nanoseconds have gone by and I haven't told my best friend/gran/someone I met on the bus last night that I'm making a piece of toast/ going to the loo/asking myself why I need to tell everyone at every moment of the day precisely what I am doing.

Or:

Set up by Jack Dorsey, Biz Stone and Evan Williams in 2006, Twitter is well on its way to becoming the new phenomenon of social networking. Sign up to this free ‘microblogging' service and you'll be able to send text messages using your phone, IM or website to large groups of people. The messages are called Tweets. As these miniature updates on your activities are limited to 140 characters Twitter is doing much for the modern art of brevity. Succinct. To the point. Nice.

You are in control of whose updates you receive, and when and how you receive them. You can switch off the updates at any point should you suddenly decide that you no longer need to know whether Dave in accounts is oogling Sandra in marketing, or if your sister is still thinking of leaving her husband.

(Oh, by the way, Barack Obama and Stephen Fry use Twitter. If you are happy to pretend that such notables are not using this technology as a marketing tool and have decided that you need such an illusion of connection to the great and the good, then I guess this is for you. Just don't expect to be invited round to dinner.)