Interesting-- someone else with the symptoms of my poor OS2008 N800...

Upon reboot my N800 also looses most of its charge (battery low warning) yet it continues to keep powered on and working for the rest of the day with wifi and Canola2.

I don't believe this issue has anything to do with the startup process, I think this is more an issue of the power management controller's firmware. It appears as if it only remembers the battery calibration data while powered on (which may attest to the fact that I may have a dead internal clock battery).

Even after checking the battery with kcbatt and battery-status console tools, the battery is at 50% or lower-- yet it just keeps on going despite the warning of 'impending doom' every five minutes.

My suggestion: turn off low battery alerts and just keep working... It's not much of a solution, but since it happens so rarely for me (I haven't had to reboot my tablet for 4 months), I just disable the warning until I get home and am able to recharge the battery.