I bought a gps receiver off a friend, all he still had was the usb charger. I'm guessing if it would work, it would be a big drain on the battery, but if I have my N800 plugged in to a wall outlet for charging, and put it in host mode, will my gps receiver be able to charge from my tablet? I have just been charging it at my desktop at home or work, but I'm going on a long road trip and don't want to have to buy a charger or take a laptop or find computers along the way. If nobody can tell me it can work, can anyone tell me if trying it could damage my tablet?

not really,

the usb port in the nit is limited (can't remember now - search !) at around 200 mAmps. If your gps draws less to charge (I seriously doubt it - usualy they draw the full 500 allowed) it could work...

buying a simple charger with an usb port (many are available) would be much more easier