Dane and others have talked about DLNA and it might still be a little vague as to what it's all about.
I found this article in PC World that explains a little more about it and thought it might be helpful. http://www.techhive.com/article/2020825/how-to-get-started-with-dlna.html#tk.nl_pwr There is an annoying video that plays at first, but read the article for more information.
