I saw the hamburgers at the back of an HGV once... 3 of them at each side.
As for the inverter, a Locost way to get one is to use and old UPS unit. Just rip the dead battery out, connect a fat lead with the lighter socket connector to the battery terminals, and make an "extension cord" from the UPS output connector to the wall socket extension. My Locost inverter did not quite work out, as the tiny 280 VA UPS gets kicked out by my laptop's PSU starting current. Though it works fine with my wife's.
