"I'm 57 years old," says Dave Grohl. "But there are still times where I feel like the little punk I was at 13. "I can still connect with that side of myself where I can scream and we can thrash, and it feels good." As if to prove it, the rock frontman has gone back to his post-grunge, punk roots on Foo Fighters' 12th album, Your Favourite Toy. He has described the record as a "powder keg", as "burning diesel", and even a spicy "jambalaya" – and it's certainly harder and faster than anything the