An effective solution is to use a server imaging program like Symantec Backup Exec System Recovery Server to create a nightly image of your system volume and your application volume (if you have one) and then use Symantec Backup Exec for Windows to backup your data volume to tape.
This way you can restore the server images to almost any hardware very quickly and then you restore the exchange data from tape.
You put the images on an external hard disk and send them offsite every day with the backup tapes.
You only need to keep a week or two of the images (allows you to roll the server OS back to a known good configuration in the event of software failure or corruption).
Good server imaging software like BESRS or Acronis can not only save your ass but save you time in other ways as well.
Well worth the spend.