I've bought the HDMI Splitter, because I want to record gameplay material from the PlayStation 4 with the Elgato Game Capture HD, and this with the HDCP encryption by Sony unfortunately (for now) is not possible (possibly is via software update still allows).
This splitter solves the problem by splitting the signal and you can as usual be PS4 take picture of the Elgato software.
Class product for each recommended only Let's Player. ;)