Perhaps this belongs in Off Topic, (and can be moved if more appropriate there) but it seemed an important topic to "General Reverse Engineering." It is actually somewhat of an update of the information contained in the article "What's behind the mm256.dat and mm2048.dat files? in the "reverser's hidden software" section of the fravia board.

This article discusses the lengths M$ has gone to maintain hidden files on your computer that record every URL you've visited (which is why when you start to type a URL in your browser you are offered choices from sites you've previously visited) and indexes every text containing file on your hard drives and maintains many/most of those files even after you thought you erased them, and even though you deleted those file and your history files, cache, and cookies from your "visible" listings..

It discusses how to make those "hidden" files visible, at least to dos, and how to get rid of them. There is also a listing of some shareware tools to accomplish these task for you, which could provide some practice for those so inclined. The article can be found at:

hxxp://fuckmicrosoft.com/content/ms-hidden-files.shtml

I would highly recommend it to those with a more paranoid bent. I know that there are forensic software packages that use these files to reconstruct your activities from what you've been doing on your computer and on the net and thought you had covered up.
(+Spl/\j, I promise not to bring this to the attention of your Misses, you're already in enough trouble over the life ambition issue.)

Food for thought and a warning to the unwary.

Regards