My 15' Macbook has been running much hotter recently doing very little, normally around 65-75*C and up to 85*C when i check it in istat pro. I'm not playing Games or anything really to trying with it, just few simple things like Skype, firefox, word and msn and it did always run this hot. I was wondering if it was full of dust or such but not sure really how to deal with it? Would it be relatively simple to clean? Would i be better off finding an apple store to sort it out? It's overheated a few times as well if i push it a bit harder with minecraft (which is when i really checked if it was overheating and lock up with a black screen and the fans running).