Stream from a networked HD?

This is probably a very easy question for most, but you can stream from a networked drive, correct? Or do you need an actual computer to stream from?
I only have laptops but after discovering Subsonic last week, I want to set up some kind of home media server.
I seem to remember seeing some networked drives, I think by WD. Would one of those work, or do you need a computer on at all times?
I only have laptops but after discovering Subsonic last week, I want to set up some kind of home media server.
I seem to remember seeing some networked drives, I think by WD. Would one of those work, or do you need a computer on at all times?