Hollywood's biggest stars George Clooney and Johnny Depp might well be in their forties but the next generation (or is that next to next gen?) isn't far behind at all.

Teenage superstars are enjoying a massive box office presence, and here's a look at the youngsters on top of the worldwide moneymaking pile:

Daniel Radcliffe and the Harry Potter gang

It's no surprise that Radcliffe, who plays Potter, along with on-screen buddies Emma Watson and Rupert Grint, are the highest earning actors under-21, with the seemingly endless JK Rowling juggernaut continuing to capture audience imaginations worldwide.

The films released so far have taken in over $4.4 billion around the world, and there are two more still to come. Wow.

Marked early on as a child actor with great promise, Dakota Fanning is now living up to that tag.

Alongside critically lauded work in films like I Am Sam, she has worked in box office blockbusters like War Of The Worlds, and her films have taken in a total of $2 billion worldwide.

Stewart, last seen at the 82nd Academy Awards, is a hugely popular actress who has balanced out indie-hipster work in films like Adventureland and Into The Wild alongside much more mainstream work, most notably the tween vampire romance, Twilight.

The latter makes up most of her filmography's $1.5 billion tally.

He hasn't been seen in too much yet, and versatility isn't Taylor Lautner's biggest strength, but appearing in films like Twilight and New Moon just when America's lapping up vampires has helped the actor's films gross over $900 million worldwide.

She might have worn a fat-suit in Little Miss Sunshine but Breslin is growing into a pretty young girl quite quickly.

A gifted actress with natural comedic timing, her films have grossed $516 million globally, at last count. Wow.

It's a pretty awesome time to be a nerd, and Cera's made that socially awkward teen thing a finely honed bit of comic genius.

Even if a mostly one-note act as a dweeby misfit, Cera's gone from TV's Arrested Development to runaway smash Superbad with ease, and his films have earned over $513 million.

Stone started out as a supporting act in essentially guy movies, but as the girl with the goofy laugh became familiar, she's become a top young actress in her own right.

Her credits include big 'male' hits like Superbad and Zombieland, and her films have made over $350 million at the box office.

A bonafide young superstar, Cyrus's earnings from her Hannah Montana television and music empire would catapult her right on top of this list, easily.

Her film career hasn't been as stellar, but Hannah Montana: The Movie ensures that her overall box office tally stands at an undeniably impressive $226 million.

Ronan, possibly the most critically lauded actress of this bunch, was last seen playing an impressive leading role in Peter Jackson's unimpressive adaptation of The Lovely Bones.

She was also quite smashing in Atonement, and her films seem to be doing well commercially too: they've made $191 million worldwide.

The third Emma on our list, Roberts is the daughter of Eric Roberts and niece to none other than Hollywood diva Julia.

With films like Nancy Drew, Aquamarine and Hotel For Dogs to her credit, the actress and singer enjoys a big tween following and her films have garnered an impressive $127 million worldwide.