It is more than just a storage device. You can add file on any type and access them from anywhere. You can also do backup. For example, I have 3 children each with his/her own share, public share (video/photography), backups, buisness files, game shares etc… and access from anywhere (they are having problems at the moment with remote access )/
Before you commit best to read this http://www.wdc.com/en/products/products.aspx?id=1140
Click on each feature (the menu line, features, spec etc) and find out if it meets your need. It does support MAC but whether you can put an app there and run it I am not sure. Although i dont see why not. Mybe Ishould try with my Windows.