I have my iPhone 3gs for 1,5 year now. I have dropped it 2-3 times from about 50cm height. Three days ago, it fell from my hands (50-60cm height) on a thin carpet in my house, it spinned in the air (5-10cm) and fell again (on the carpet). When I got it in my hands I saw that it had switched off. I turned it on and it took ages to startup (about 1') and the date was reset to 1970. For the last 3 days now, it keeps switching off randomly. It doesn't matter if I move it violently or softly, the switch-offs are totally random and happen about 4-7 times/day. What's notable is that the date doesn't reset to 1970 all the times. I am thinking that since it switched off when it fell in the first time, maybe that moment the battery had moved a little from it's position and every now and then it loses it's contact and keeps turning off on it's own. Do you find my guess possible? I'll probably open it and check to see if something has moved (although I find it really hard for an inexperienced person as I to notice a slight misplacement of the device's interiors).