Mail Server. After being unseated as top product in last year's contest, Microsoft Exchange Server is back in the saddle, with Exchange Server 2003 winning the award for Best Mail Server. The most recent version of Exchange offers improved clustering and backup features, and the impending release of Service Pack 2 (SP2) promises extended functionality for mobile users. The past year's introduction of several free add-ons—the Exchange Intelligent Message Filter (IMF) and Exchange Server Best Practices Analyzer—have no doubt made Exchange 2003 even more attractive to users and administrators alike.