PCNation.com has the Buffalo LinkStation Pro Duo 2TB NAS (model no. Q81800) for $299.97, which is $390.02 off the original price of $689.99 and the lowest price we have seen on this storage device by about $20.  FREE shipping is included and sales tax applies for residents of California, Illinois, Massachusetts.

The HP Media Vault mv2120 500GB storage unit is priced at $199.99 after an $80 mail in rebate at HP.com.

Newegg.com is offering the Netgear 500GB network storage drive for $264.99 (after mail in rebate) with FREE shipping.

The Buffalo LinkStation Pro Duio is a 2-drive (2 x 1TB) NAS solution that can be configured in RAID 0 for performance or RAID 1 for redundant storage.  If one drive fails, the other retains a copy of the data.  This storage device is compatible with both Windows and Mac based operating systems.  Included is a one year warranty on parts and labor from Buffalo.  Dimensions: (H) 6.4" x (W) 3.9" x (D) 8.7" ; weight 6.8lbs.