Iconize all windows apart from the active one.

I have many application windows opened at once. Let's say: a web browser, a picture viewer, a word processor, ... I can shift from one to another by pressing Alt+Tab or clicking on the icon bar, or I can activate a new application by the Start menu. The new window will go over the previous ones, and my desktop is a bit similar to my real table, cluttered with many open papers and books.
I wonder if an utility exists, that iconizes all the windows except for the newly activated one, thus leaving the screen background visible, all but a portion occupied by one window.
Thanks to everyone.