London, Feb 28 : The tools of "Web 2.0" - the community-driven web - can change the world, a meeting heard this week.

Delegates at the Terra future conference in London were told that social networks can really make a difference, and Barack Obama''s election campaign believes the notion.

Last year, tech guru Tim O''Reilly, founder of O''Reilly Media, defied the Web 2.0 community to give something more productive than the `useless' Facebook applications.

Now, at this week''s conference, UK-based social media consultant Chris Thorpe pointed out that just a month after O''Reilly''s call, the Obama election campaign launched the Obama ''08 iPhone application.

The application organised and prioritised contacts in key battleground states, "making it easy [for campaigners] to reach out and make an impact quickly", reports New Scientist.

Thorpe told the conference about a number of other networking sites that might satisfy O''Reilly''s challenge.

Accesscity, for example, is a social networking site through which a community of Londoners is helping to identify the simplest routes across the city for those with mobility issues - be it pushing a baby buggy to carrying heavy bags. (ANI)