Chris, yeah you can Use your Lacie drive as a NAS on your network for all to stream from. As for HD streaming, I've streamed high def rips over stock cat5 so you should be okay there.

Nick, there are a few wireless media players about and all they do is connect to your network and allow you to stream from files stored on a NAS or computer also on your network. No real difference to what we aretalking about here, other than it's wireless. Which isn't really going to cut it for streaming high def stuff unless all the wifi gear is 802.11n spec, and even then, drop outs spoil fun!