Mac OS X 10.8 QuickLook Causing CPU & Temperature Spikes
It's a bug for sure, but the root-cause is a cached search in Finder which tries to find every file on the system and runs out of resource handles or something.
It's an obvious use-case in Finder that I'm astonished nobody has spotted yet (but I have been a Unix/Linux system developer for 20 years).

When Finder is doing it, you can both get rid of the phantom 'suck search' immediately, but also fix it permanently with 2 button clicks:-

When you have the issue, on the finder menu bar, you'll see the 4 icons pertaining to switching views, list, columns, coverflow,  etc.

Just click one of the buttons once to change the view to something else from your usual default, then click the button pertaining to your default view preference to change it back.

You should notice 3 things:-


The CPU-spin stops immediately and normality returns.
The phantom stuck search gets removed
It doesn't happen again - of course until you exercise the Finder design flaw (that's been there, what 7 years now!?!?) again. Just repeat until somebody wakes up and figures it out.


-Al.