This is a great example of “social” programming, finding patterns in the data which adapt themselves to a particular user. This application when added to Outlook helps you prioritize and organize your inbox.
According to Microsoft, “the process on which SNARF is based is called social sorting. The concept has been around for a while; in fact, Microsoft Research’s Eric Horvitz worked on a similar project called Priorities a few years back. But what’s new about this implementation is its simplicity. The tool, which has been deployed within Microsoft for a field study, simply counts e-mails, sorts them by sender, and draws conclusions about their relative importance from the intensity of the correspondence relationship.”
The link gives you instructions to download the program.