Data Protection Manager 2007 Volume Sizing Tool
"DPMvolumeSizing" is a tool-set that eases the process of gathering data for DPM volume sizing purposes and apply DPM sizing rules to obtain DPM replica and recovery point volume requirements. Scripts collect (local or remote) and save information in a format tuned to easily import into an Excel workbook and is detailed in the user guide. The tool-set is validated to work for the DPM; SQL Server, Virtual Server, Exchange Server 2007, Volume and System State protection workloads.
Get it here: http://www.microsoft.com/downloads/details.aspx?familyid=445BC0CD-FC93-480D-98F0-3A5FB05D18D0&displaylang=en