i am thinking of doing battery mod, remove the keyboard, fit a (or 2 or 3) massive battery/(ies). i had a 1800 maH (same as BL-5J) battery from a phone (B369) that was built by an Indian manufacturer LEMON that could be used in nokia n900 but without the back cover and my device showed like 900 maH in the status menu, device does not show values greater than what original battery had. i want to fit two or three of them but there is a problem, my device is in a very good condition so i will be looking for another one in coming days.