There are hidden files called index.dat files which store the URL's of EVERY webpage that has ever been viewed on your computer. These URLs are not erased by using the usual user-available tools. You can download the file viewer at this URL:http://www.pointstone.com/products/index.dat-Viewer/ at no cost. However, the privacy program that erases the entries is $29.95.
The following is from the 'Readme' file for a program which reads these hidden files:
What are Index.dat Files?
Index.dat are files hidden on your computer that contain all of the Web
sites that you have ever visited. Every URL, cookies and browsing history
is listed there. The file names and locations depend on what version of
Internet Explorer you have. If you are running IE version 4.0 or above,
the file name is "index.dat". Microsoft has not supplied an adequate
explanation as to what these files are for or why they have been hidden so
well.
What is index.dat Viewer?
index.dat Viewer reads the index.dat files directly. This makes sure that
what you see displayed by the program are the exact contents of the
index.dat files.
If you encounter a bug in index.dat Viewer, please visit
http://www.pointstone.com/support/ and feel free to submit details about
the problem, or your general feedback about index.dat Viewer.