The 351UNE box from NDAS is a great little network-attached hard drive. It's fast (1Gig network speed), flexible (network, USB, and eSATA connectors), and easy to setup & use. It comes in a variety of sizes, and you can even buy it from local dealers without a HDrive and add your own (I got mine at Fry's for $60.
If you get one, make sure you get the updated drivers from their website (V3.71 as of this post: http://www.ximeta.com and click on "NDAS DRIVER for Windows"); the older drivers do not work so well.
Even better, their technical support was astounding: I was working on a Saturday installing a couple of drives for a client and couldn't get them to work (older drivers that came with the hardware). I sent an email to tech support, fully expecting to have to wait until Monday morning for a response. Within about 20 minutes, I got phone call (!) from their sales rep. He apologized for not being a tech, but offered to do what he could. What he did was point me to the new drivers and - voila - everything was up and running.
Now that's a terrific combination: great product and even greater support...