You may be sceptical about the value of being on Facebook. Yes, it is a largely-pointless and addictive procrastination tool. But there are strong arguments for signing up. And if you get sick of it you can always quit, although deleting an account is not as simple as it looks. But it has been nicely described as “a giant lobster trap with your friends as bait.”

Bear in mind, though, that you must set up your privacy so your personal details are not shared with the entire internet (more on that here). And be careful about sharing some personal details with anyone: a man in Wales was sentenced to prison for murdering his partner after she changed her relationship status on Facebook to “single.”

What can Facebook be useful for?

• Organising a non-profit group, with event scheduling, announcements, and a photo gallery
• Setting up a site for your band, allowing Facebookers to become fans and watch your videos
• Sharing photos with a semi-private group of people, not the whole world (though again, this requires careful use of the privacy settings)
• Maintaining contact with people who live far away, via the background noise of their daily activities
• And last, but not least, it keeps track of birthdays for you

Many of these activities, though, could equally be done by other technology: blogs, RSS feeds, DIY social network sites like Ning.com, and Flickr. There’s a certain danger in putting all your eggs in one basket. Facebook is currently privately owned, but who knows who’s going to to buy it? Rupert Murdoch paif half a billion dollars for MySpace. What happens to your personal data then? Social networks rise and fall, and in a few years Facebook may well be as uncool as Friendster.