If you have Windows Vista, 7 or 8, you can stream over the network using a Media Center Extender (Linksys, D-Link, HP, Ceton) or XBOX (Win 8 only works with XBOX for now).
If you have a DLNA enabled player or TV, you can set Windows to be a DLNA server in the background.
6 TV's in the house on FiOS and we only pay $4.99/month to connect them all!!! Power to the CableCard and WMC7!!!