One useful suggestion which should be easy enough to include in settings or a status area switch if BME replacement is installed is a simple recognition of the obvious problem killing N900s, the USB port.
Quite often the port is ripped out but it is still possible to solder connect the positive and negative terminals but not the data pins, there is also the users who have hacked in a inductive charging system. Right now the only option is to bypass the charging system in the phone and use a battery charge manager circuit stuffed under the battery cover and soldered direct to the battery pins.
There is some discussion of turning off the data pin short while still having charge management in this thread http://talk.maemo.org/showthread.php?t=93289&page=2

apparently all that is required with BME replacement installed is: