40 This year sees one of the greenest music tours so far hitting Hyde Park. Jack Johnson will headline a concert on 2 July, and has pledged to make his tour the greenest in music history. To improve eco-awareness among his fans, Johnson has helped to set up a new interactive community, All At Once, online at jackjohnsonmusic.com and at www.allatonce.org, to provide information, tools and motivation to create change. And if you are planning any summer festivals, try to take the train or at least car share wherever possible.