Using your voice to recharge mobile phone batteries

I was thinking if it would be possible to use the voice as a source of energy in the mobile phones whereby part of the energy from phone conversations can be converted into energy for phone battery recharge or one can sing along to music (mp3) from new music player type mobile phones and have this sound energy converted into electricity and be stored on the phone batteries for later use. Even shaking or tapping on the phone keypad could be used as energy input for mobile phone battery recharge…