Over the past month my MacBook has become noticeably slow and hot. Many of my applications take forever to load. The laptop is also very hot on my lap and the fan is always running at mid to high speeds. For example, my computer has been idle for the past 20 mins and the temp is currently at 145 F. I also have plenty of HD space free for swap files. Currently running 10.6.7 on 2.2 GHz with 2 GB RAM. Activity monitor shows 80-90% idle when I'm not doing anything (and still running hot). No major software changes or extra background apps for at least 2 months.