I have am having a recurring problem with my CPU maxxing out.
Using System Monitor I can see that the CPU cycles from 15% to 100% then back again every couple of seconds, the graph is going up and down continually even when no programs are running. This of course generates heat which causes the fan to spin all the time and so uses more power than necessary, it also slows program response time.
I typed 'sudo top' into terminal and it appears that something called 'upowerd' is the culprit. I believe that this controls my Touchpad and cannot just uninstall it.
I tried disabling some small things like Wobbly Windows and Shift Switchers which appeared to help for a while but the problem is back.
Xorg and Compiz use about 6 to 7% of CPU power each and are the next highest users after upowerd.
I am using a Sony Vaio laptop, dual core Intel T2300 @1.66Ghz, 2Gig RAM with Linux Mint 10 Kernel 126.96.36.199-generic, Gnome 2.32.0