The Telegraph claims, in an article that sounds unlikely to me, that mobile phones could soon be charged by talking into the handset:

Electrical engineers have developed a new technique for turning sound into electricity, allowing a mobile to be powered up while its user holds a conversation.

The technology would also be able to harness background noise and even music to charge a phone while it is not in use.

If true, this is also good news for The Telegraph itself. Assuming we really can generate electricity by talking hot air, the newspaper’s HQ could become the Middle East of generating electricity by the power of regularly spouting garbage at volume.