Power in the 21st century comes in many forms, but one thing is certain, it no longer relates simply to pounds in the bank. The internet has given any individual the power to influence millions with a single Tweet, the power to self-publish a manifesto and the power to reach a huge audience in seconds, which brings a whole new meaning to net worth. It also means that the gossip mill has gone global. What might once have passed the masses by can become international news, a hot topic up for worldwide discussion.

So, who are the new power players in this speeded-up, digital landscape? We spoke to experts in entertainment, fashion, the arts, business, media, politics and sport to compile a long list of the most influential names in each field. The only criteria we gave was that they must be British and under the age of 30 — the careers of the Noughties generation having flourished under BlackBerry rule. Then, using a formula devised by Philip Beresford, compiler of The Sunday Times Rich List, we number-crunched the list to come up with our New Power 30.

Google hits, Twitter influence, Wikipedia references and digital column inches were all taken into account, as were the number of campaigns, charitable and otherwise, and endorsements our influentials have racked up. Friends in high places add clout, as does paparazzi presence. What emerged was a list of obvious movers and shakers (you would have to have been in a coma to have missed their output this past decade), but with a few glaring omissions. Girl of the moment Cheryl Cole scrapes in as runner-up in the entertainment section, for example — but, then, she is yet to break America, key to upping your Google profile. Witness Robert Pattinson’s 15m Google hits off the back of one film. And infamy has currency. When Mounir Moufarrige was looking for a celebrity to inject new life into the house of Emanuel Ungaro, he asked for the most-Googled girl around. Step up Lindsay Lohan. Our British equivalent is Amy Winehouse, topping the entertainment list. She has our attention, but the question now is whether she will squander the power that comes with an international audience of millions.

And anybody who wants to maintain their position at the top will have to keep the public interested. One way is to diversify, so Lily Cole’s move into acting is a savvy one. In the arts, your work must have talkability, while in sport, your spouse, brand appeal and eye for a hot Hollywood connection (see Ashley Cole, who recently invested in a film starring 50 Cent) can count far more than medals. Meanwhile, Prince William tops everybody on our list in terms of Google hits and column inches. Interesting in a society where the royal family is seen as increasingly irrelevant. William knows that there is no point having power if you don’t put it to good use. He has said he wants to be more than a “royal ornament”, and is dedicated to his charitable causes. Only the next decade will tell what the rest of our Power 30 decide to do with theirs.

Entertainment

1 Amy Winehouse, 26, singer

All eyes are on Amy — again. She’s got to the top as the car crash we can’t look away from (only Wayne Rooney and Prince William have more digital column inches), but everything rests on her next move. Can she get clean? Will her protégée Dionne Bromfield amount to anything? Will her long-awaited third album bomb? If she can emerge triumphant from her troubles, she will be a force to be reckoned with. Max Clifford says: “Amy will never disappear, she’s too established. If her next record doesn’t work, she should look for a cause to attach herself to.”

2 Lily Allen, 24, singer

The ultimate power player, Allen has aligned herself with older influences — from Jay Jopling and Kate Moss to Chemical Brother Ed Simons. She also epitomises the new I’ll-try-my-hand-at-anything approach. So when the new face of Chanel says she is giving up music, you know she is planning something. Karl Lagerfeld chose her for Chanel because, “she is a self-made woman, cool, young and extremely witty”.

3 Keira Knightley, 24, actor

At 20, Knightley was the third-youngest actress ever to be Oscar-nominated; she was also nominated for a Golden Globe and Bafta for Atonement. Next month, Knightley, worth £27m, makes her West End debut in The Misanthrope. She is also is big on the charity circuit, supporting Amnesty International and campaigning against domestic violence. “Keira embodies a kind of Englishness that seems to resonate, particularly with American audiences,” says Ian Freer of Empire. “As she gets older, she will only become more interesting.”

4 Emma Watson, 19, actor

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