I have a white macbook, which still has around 6 months of applecare. Twice in the last few months I have had my hard drive start making a clicking noise and then the computer will not do anything. I force shut it down and then try to restart, this fails, and sometimes show the flashing folder and "?" icon. After waiting about 30 minutes the computer will boot as normal. I have a good back up of everything, but I would prefer not to have to deal with replacing the hard drive during the upcoming semester. If anyone has experience with this do you know if Apple will replace the hard drive even though the S.M.A.R.T status is verified and the computer appears to function normally at the current time.