removing the logo:
http://www.blackberryforums.com/gene...ular-logo.html
One other way to remove the logo is to rub it off with a sugar cube, as the cube is rough enough to remove the paint but not hard enough to scratch the plastic of the phone. This is an older more primative way of doing it, the method in the thread I just linked sounds more effective.
This will not only be the cheapest way to get a plain black 8800 it will probably be the easiest. I havnt seen any sign that RIM is selling the real unbranded 8800 yet. Send me a PM if you are interested in getting a tmo 8800.