Phones-off Fridays 'Last Friday I did the unthinkable - I switched off my mobile phone. At first there was the separation anxiety, not unlike the cravings one feels when on a diet, that insatiable yearning for something you know you can't have. Then there was the involuntary impulse to reach into my pocket to check the phone for a text message, email or a missed call. Every look at the blank screen was disappointing.'