After using my N800 daily for about 18 months, bad things have started to happen, the most concerning is that the touch screen randomly stop responding, and I can only get it back by rebooting.
This is now climbing up the serious scale as its happening several times a day now. Combined with random reboots (it seems if I leave it alone for a while its decides to reboot itself, maybe out of boredom?) and dreadfully slow web access, my N800 enjoyment is going down hill rapidly.
I've updated to the new firmware, removed the internal SD cards etc, but nothing seems to change this behaviour.

Any clues? or is this the death throws?

BT

Sounds to me like you need to call Nokia's service department. That sounds more serious than a broken part that needs replacing.