Well my plans were to move my HTPC media to them, which is streamed to my HTPC's daily. I typically transfer new media to my NAS every once in a while, so it could end up being several hundred gigabytes. Though I could transfer every time I get new media, so the size would be considerably less. Alternatively if that isn't an ideal use for them, they could be storage for all my other files which currently reside on over a dozen drives that are not in the NAS. Those files would be accessed rarely unlike the HTPC media, and would only see small amounts of data added irregularly.