I spent a lot of time messing with an HDMI splitter as well as a wireless HDMI transmitter (that I eventually ditched in favor of a 100' HDMI cable that I need to install...)
There are 2 kinds of HDMI splitters - active and passive.
When I say active and passive, I could be overstating for simplicity, they could actually both be active, but it is easier than saying "the cheap kind and the expensive kind." And mind you the expensive is not that expensive when you consider the alternative.
I went with this initially because I thought it would be one less power connection to deal with:
http://www.monoprice.com/products/p...roducts/product.asp?c_id=109&cp_id=10113&cs_id=1011306&p_id=8153&seq=1&format=2
Looked like a pretty siple y-adapter. But what they don't show you in the picture is that there is also a power adapter that you have to use. It kept cutting out with the wireless HDMI device. I would lose the signal on the sending end.
Then a friend gave me one of these:
http://www.monoprice.com/products/p...roducts/product.asp?c_id=109&cp_id=10113&cs_id=1011306&p_id=8204&seq=1&format=2
Now suddenly I had a strong signal and the HDMI never went out, not once. However the signal on the wireless unit was just too weak outside and I was getting terrible pixelation.
I held on to the wireless unit, I might use it in another place in the house, but essentially putting the better splitter on and the 100' cable cleared everything up and I essentially had a tivo mini out in the shack for the price of a cable, an IR relay and splitter (under ~$160).
When I tried to run the component to the TV and the HDMI out to the shack I was receiving error messages on the inside TV. I need to try that again some time to see if a splitter is even needed at all.