My iPhone 3g, 3 weeks old and battery around 95%, was working fine until suddenly the screen was black no matter what I did. I tried to restart it, held down every button one by one for 20 seconds, nothing. Nothing would bring the screen back on. But when my friend called me it would ring, and I would try to answer it by sliding the slider (which I couldn't see but of course I know where it is and can do it with my eyes closed) and nothing would happen. So the screen was black and wasn't responding. After 5 minutes or so, the restart button suddenly worked and voila, but iphone was fine. What gives? Anyone had this experience before?