My laptop started heating more and more until at some point I had to start forcing it to "Sleep". (it has Vista on it)
At some point I got really aggravated by that fact and started investigating. Forums revealed that the issue could be linked to heavy processor usage.
Process Explorer showed that I had some wierd behavior even when the machine was idle (Indexing service is disabled - dummest thing ever) - explorer.exe taking 100% for 5-10 seconds.
There was a wierd dll doing that (SHLWAPI.DLL):
At some forum I found out that this was related to the start menu search. WTF?
It comes out that the start menu search (which I find one of the few useful things that come with Vista) does a search in the index first and then goes the the hard drive.
We don't want that.
There is an option in the start menu settings which stops that - problem solved.