I've been monitoring the CPU temperatures on my 2 week old alu macbook frequently, and it always hovers at ~42 degrees celsius. However, today something odd happened, all of a sudden the computer was getting noticeable hotter (the fans remained off though), when I checked CPU temp it was up to 72 degrees. I checked with "Activity Monitor" and nothing was using up more than 2% CPU. Then I saw through iStatPro that system CPU usage was at 40%. What the hell? Its usually at 2-5%...i.e. always. After restarting, the system cpu usage was back down to 2% and the temperature slowly dropped back to its norm. Anyone have this happen?