Two other subjects that come to mind as possible alternatives that I'll mention, and answer in more detail if there is any interest.
One is the issue of data/drive redundancy, and how that often drives up the minimum hardware price. This is a low(er) cost solution that a couple of clients are testing now with good results so far:
http://www.drobo.com/products/drobo.phpYou choose the size drives you want, attach the device to your machine, then load the raw drives that you will use to make up the array.
I have clients with 100's of GIGs of data, so they can either un-mount the array and 1)take it off-site, or even 2)eject a drive in mirror and take it with them. Another client runs a weekly tape job from the array, and takes that tape off-site on Friday.
Related subject, if money is tight for the practice, a Linux server running Samba can network share NTFS or FAT32 disk space, (and a wide variety of other features/services as well) such that the Windows machines never know the difference. With the latest version of Unbuntu, I'd say that ease of use of server features is about the same.
The last may get me called out a heretic, but for someone trying to bootstrap a small practice, it has the potential to skip the software costs associated with bringing up a file server.
