My question is exactly the title of the thread... Is it possible to use a second (internal) drive in a mac pro as the Time Machine backup drive for a MacBook Pro? This would be, I hope, something like backing up the MBP wirelessly to an external drive connected to an AirPort Extreme. The difference, of course, would be that both the backup drive and the requisite wireless bits would all be in the Mac Pro. Sounds like it ought to work, but that's not saying much. Anyone have experience with this? Thanks!