Mounting and fixing a supposedly unmountable and unfixable hard drive - As described in this MacFixIt Forums thread (http://www.macfixit.com/ultimate/Forum3/HTML/007164.html), a user was unable to startup his Mac whenever a certain drive was attached, regardless of whether or not it was the startup drive. An Apple Authorized Service Provider told him it was hopeless and the drive needed to be replaced. It turned out (as also suggested in this MacFixIt Forums thread - http://www.macfixit.com/ultimate/Forum1/HTML/003466.html) that the drive was saved (although not the data on it) by starting up the Mac from the Linux OS.