MTBF (Mean Time Between Failures) sandbox utility has been around since R5.
The down time reported for crashes works fine, but the down time reported for server shutdowns is not working in Domino 8. It typically reports 0 minutes down and occasionally a value of at or near max Int ...
MTBF is available for Windows 32 and Windows 64 bit server OS. It's a great tool. Make it available for the other server operating systems. Then get it added to the standard server install kit (posted in an earlier idea) http://ideajam.net/IdeaJam/P/ij.nsf/0/18FF27F7170AFEF586257862000D129E