For people concerned about files and items left on their machine. I was browsing on the wilderssecurity site and found:
"MRU-Blaster is an all-new program, made to do one large task - detect and clean MRU (most recently used) lists on your computer. These MRU lists contain information such as the names and/or locations of the last files you have accessed. But they are located ALL OVER your registry, and for almost ANY file type. By looking at these MRU lists, someone could determine what files you opened/saved/looked at, what their file names were, and much more! (And, in many cases, the lists are displayed in drop-down menus automatically.)
MRU-Blaster is constantly updated to clean new MRUs as they are discovered!"
I'm not bothered on way or the other about things on my machines but others, for all sorts or reasons, are. This may be the thing for you.