I am thinking of getting a WHS as an easy way to have expandable backup (mirrored) storage.  I have considered NAS drives but they dont seem to have the expandibility (at the same cost) as WHS.

My main concern is power consuption from an always on server.  The system will be basic (probably a Celeron chip, 1gb ram and 2 hard disks).

Does WHS have a power down, wake on lan type function?

Anything else I should think of when buying?