My Nokia 6680 had exhausted empty battery for a few weeks (needed unlock code ;)) When I tried to switch it on, I was surprised - it wont boot, no screen blinking, not a single sign of life! Battery wont charge (well it won`t show any charging indicator). But as I have Nokia charger with LED light in it, I can see the charger blink when I attach it to the cellphone - some hope for getting it back working without taking it to service ;) So I remembered the hard reset code for N6680 (or any other bb5 nokia) and gave it a try - guess what, my phone was back from the grave :)