I live in a new place where the AC/furnace and surrounding area has a way of letting a lot of dust/lint, in the townhouses. I can clean my desktop and the next day I can write my name with my finger in the dust. I keep my MBP closed but since I work from home and it is usually open I think it needs to be cleaned out. Is this something I can do if I am careful, have a can of compressed air and try to use it to clean the fans out without turning the blades and possibly taking off the back to get the areas free as much as I can. I have heard that taking of the back voids the warranty, but I think I can handle removing the back and using the compressed air lightly while trying to get rid of the dust. I have a feeling that this accumulation of dust/lint is what causes my MBP when I am watching some noes videos to run really hot. any suggestions on this and other things I can do to clean the MBP and do a straight-forward maintaince check-up on the machine? does restarting while holding down the shift key do any kind of maintaince? I know it boots it in to Safe mode but there is a wand-type device below the moving gear while it is dong its thing when I hold down the shift key that shows some progress happening with something. Is this wand stick that slowly fills up as the reboot moves along telling me anything? I know you do not need the install disk to use the disk utility but when I use the disk utility without using the DVD to boot to, the permissions are not repaired. If I boot up using the disk, the Disk Utility pretty much takes care of all of the permissions. any other maintaince stuff that I should be doing? thanks I should say I do have Applecare but I called the Apple Store and they did not sound too excited about using compressed air to clean out the inside of the machine. Not sure if this was something they do not want to spend time on or what the reason was for their reaction to my request.