Not quite on topic, but perhaps germane.....

I'm dealing with a similar issue: two computers and wanting to share and backup data. However, I'm using ethernet for DSL, printer and the two computers through a Linksys workgroup switch. This makes NAS (Network accessed storage) a logical choice. As I've researched, a NAS storage appliance with a single hard drive would work. However, to "future-proof" the job, I'm looking at a NAS enclosure with RAID and a couple of hard drives. RAID allows the NAS hard drives to coordinate in a number of different ways, including total redundancy.