You plug in your SGS to your computer's USB port. It tells you USB is connected and starts charging. You go to the home screen, swipe down and select 'mount drive(s)'. You copy/move your files and come back to your SGS an hour later. There's a message saying 'Battery fully charged, unplug your phone'. You unplug your phone and then realize duh!!!! You forgot to unmount the drive(s). Naughty naughty Samsung!