Orange, the official Communications Partner for the Glastonbury Festival, today announced the latest invention in the world of mobile charging technology with an innovative gadget that powers mobile phones using sound. Following months of planning and development, the prototype, named the Orange ‘Sound Charge’ has been produced in conjunction with renewable energy experts at GotWind. The eco charging device uses an existing technology in a revolutionary way; by reversing the use of a product called Piezoelectric film, allowing people to charge their mobile phones whilst enjoying their favorite headline act at Glastonbury. It’s an interesting concept, we’re not sure about the design or just how long you might be able…