Without knowing what constitutes "appropriate" in the context of your question and in the absence of specific requirements, I would have to say there are a number of possibilities. If you are referring to RAID 1 mirroring, Windows 2000 Server Edition supports software mirroring at the OS level.
If you are looking for a noncontinuous (point-in-time) type of mirroring, Store-Age, FolderClone, ViceVersa, rReplicator, and many others offer local or remote data mirroring solutions. There are also utilities that allow you to copy data from on location to another such as Robocopy or xcopy but these are not considered mirroring utilities.
One word of caution however: If you are considering OS-based RAID 1 mirroring (real time and continuous), you might want to make sure that the disk devices (source and destination) offer similar performance to avoid introducing a bottleneck.
This was first published in September 2004