Anybody thought about having hardware failure? Then it would not matter what OS or how stable software it is... and it still crashes. In PC world most common HW failures causing crashes have been memory sticks and power supply issues. Why couldn't this be the case with N800 as well? It is not out of question having a bad solder joint, for example, that makes sometimes no contact, and would cause hangup or crash/reboot.

I have N800 and I have found it to be very reliable so far. If you are experiencing frequent crashes I'd suspect actual hardware being faulty?