In this demo I am going to walk you through setting up one of those alternatives, called FreeNAS.FreeNAS, as you might have been able to garner from its name, is free open source NAS software that is pretty robust.
It supports CIFS/SB, FTP, NFS, RSYNC SSH, AFP, Unison, UPnP, ISCSI, local and Microsoft Active Directory authentication, SoftRAID, disk encryption, and has a WebGUI interface. FreeNAS can also be configured to run off a USB Key to keep all that hard drive space for storage. It is built on the FreeBSD platform but you won’t need to know any Linux to get it up and running.
For this demo I am going to setup a RAID 1 drive and make it so I can access it from Windows Vista.
The step-by-step instructions are really easy to follow, with many screenshots.