Bitcoin is a peer-to-peer monetary system in which all transaction records are public. Participants can use its open-source software to transfer virtual currency to one another as easily as they might send an email. Bitcoin opens an uncharted world of new possibilities to explore. We'll follow the stories of entrepreneurs and startups that are helping shape the new financial frontier. We'll look at the competitive mining market and the various subcultures within the Bitcoin community." You'll encounter a variety of characters and opinions as we examine the social and political impact of an open-source digital currency. Will the rise of Bitcoin bring a monetary paradigm shift that will forever change the world? Supposedly invented by a mysterious Japanese man named Satoshi Nakamoto (whose current whereabouts are unknown). Because it is designed to have an absolute ceiling of 21 million Bitcoins in circulation (not anticipated until 2040), and the system has no central depository or administrative authority, it has great appeal to libertarians and others who seek alternatives to a perceived corrupt, manipulative banking infrastructure and excessive government regulations. Its low processing fees compared with those of mainstream credit-card companies also hold considerable allure for merchants.

Julien Temple's epic time-travelling voyage to the heart of his hometown. From musicians, writers and artists to dangerous thinkers, political radicals and above all ordinary people, this is the story of London's immigrants, its bohemians and how together they changed the city forever. Reaching back to the dawn of film in London at the start of the 20th century, the story unfolds through film archive, voices of Londoners past and present and the flow of popular music across the century; a stream of urban consciousness, like the river which flows through its heart. It ends now, as London prepares to welcome the world to the 2012 Olympics.

Sir David Attenborough reveals plants as they have never been seen before - on the move and dangerously devious. About the major problems of life - growing, finding food, reproduction - and the varied ways plants have evolved to solve it. Filmed from the plant's point of view, using computer animations, fibre-optics and unique time-lapse photography. The first episode looks at how plants are able to move". The bramble is an aggressive example: it advances forcefully from side to side and, once settled on its course, there is little that can stand in its way. An altogether faster species is the birdcage plant, which inhabits Californian sand dunes. When its location becomes exposed, it shifts at great speed to another one with the assistance of wind — and it is this that allows many forms of vegetation to distribute their seeds. While not strictly a plant, the spores of fungi are also spread in a similar fashion. One of the most successful (and intricate) flowers to use the wind is the dandelion, whose seeds travel with the aid of 'parachutes'. They are needed to travel miles away from their parents, who are too densely packed to allow any new arrivals. Trees have the advantage of height to send their seeds further, and the cottonwood is shown as a specialist in this regard. The humidity of the tropical rainforest creates transportation problems, and the liana-species Alsomitra macrocarpa is one plant whose seeds are aerodynamic 'gliders'. Some, such as those of the sycamore, take the form of 'helicopters', while others, such as the squirting cucumber release their seeds by 'exploding'. Water is also a widely used method of propulsion. The tropical sea bean Entada gigas has one of the biggest fruits of all plants and is dispersed by water streams. However, most plants use living couriers, whether they be dogs, humans and other primates, ants or birds, etc., and to that end, they use colour and smell to signify when they are ripe for picking.

The rise of alternative rock in the USA. From its early underground days where bands like Black Flag drew inspiration from the DIY ethos of punk. We explore why the bands that emerged from the underground offered an alternative both to the established music industry and the prevailing politics. Bands like R.E.M., The Pixies and Husker Du, REM breaking into the mainstream charts with 'Losing My Religion', Seattle 'grunge' scene, culminating in the success of Nirvana's 'Nevermind'

Spring arrives in the polar regions, and the sun appears after an absence of five months; warmth and life return to these magical ice worlds - the greatest seasonal transformation on our planet is underway. Male Adelie penguins arrive in Antarctica to build their nests - it takes a good property to attract the best mates and the males will stop at nothing to better their rivals! But these early birds face the fiercest storms on the planet. In the Arctic, a polar bear mother is hunting with her cubs. Inland, the frozen rivers start to break up and billions of tons of ice are swept downstream in the greatest of polar spectacles. This melt-water fertilizes the Arctic Ocean, feeding vast shoals of Arctic cod and narwhal. The influx of freshwater accelerates the breakup of the sea-ice - an area of ice the size of Australia will soon vanish from the Arctic. On land, a woolly bear caterpillar emerges from the snow having spent the winter frozen solid. Caterpillars normally become moths within months of hatching, but life is so harsh here that the woolly bear takes 14 years to reach adulthood. Once mature it has only days to find a mate before it dies! Alongside the caterpillars white Arctic wolves race to raise their adorable cubs before the cold returns.

The 25 October 2009 concert in Pasadena, California was streamed live on U2's YouTube channel, the first time a concert was streamed live on YouTube. Over 10 million viewers streamed the concert, making it the largest streaming event in the website's history. The shoot was directed by Tom Krueger, who had previously worked with the band on the film U2 3D.