from googling about HAVA
"You hook your settop box (TV system) or, really, any video source like a DVD player, into the back. As long as you have an 802.11g network (must be “G”, not just the older “B”) it’ll work fine. You load some software on each client to view the video. Windows only today, but they are working on Macintosh versions. They are also working on mobile versions for Windows Mobile and Symbian (due around September)."