Tong Family

Well this is interesting. Since HDMI is actually digital, folks have been building transceivers that take say the HDMI from a Tivo and its IR and hauling it over CAT5 or CAT6 to a device far away. 
The system we use is quite flaky with audio and video and seems to lose synchronization so you have to unplug the transmitter. Mux Labs Econo Plus HDMI Extender. It costs $228 so pretty expensive. It runs 45m over Cat-5e at 1080p. On Amazon, the top seller is just $80 for a pair or spend $300 for a highly rated extender by Atlona as the cheaper ones drop out.
Then there is a whole new class of devices called HDMI over IP. This was introduced in early 2009 by Just Add Power. This is really interesting if you have enough bandwidth. Particularly if you have Ethernet switch that does fast switching. So a good chance to create a separate virtual vLAN and then you have one Tivo that can connect to lots of televisions 🙂 But creating multiple VLANs, you can one HDMI transmitter and then on the receiving end have an HDMI receiver for each source. Kind of a neat architecture.
Turns out you need 48Mbps to transmit full Blu-Ray 1080p so that saturates 100Mbps Ethernet. But with the new gigabit switches that is less of a problem and certainly less with dedicated vLAN. The new JustAddPower 2G devices use Gigabit ethernet so that it doesn’t need to compress at Blu-Ray resolutions. It is expensive thought at $600 per receiver and transmitter (so $1200 at least!).