Here is how SampleApp hardware configuration looks like.
It consists of FEZ Domino, FEZ Mini and FEZ Cobra. All board have a LED connected: Domino green, Mini red, Cobra yellow. All boards have a Nordic wireless module. the communication order is this:
Domino board has a variable resistor connected that is used to set the delay in transmitting the packets. The video shows the SampleApp code running.