I just noticed a way to drastically reduce temperatures in my PowerBook, without much of a downfall in performance! I always have the CPU speed set to auto in System Preferences, but I set it to reduced, and noticed pretty much no difference in performance, but temps have dropped 10-15* F! After about an hour of web browsing on reduced, the CPU temp reports as 119* F, wheras on auto it's closer to 125-30* F!!