The low power used by the RPi3 makes it attractive for some telecommunications tasks.
We are having trouble finding a mounting or case for one or more RPi3s which would fit in a 19in rack.
In the worst case we'll use a shelf, but a more secure mounting would be very appreciated as then we could run the RPi3s caseless for better cooling.
In an ideal world that system would also include dual AC power supples feeding a common DC bus to which the RPi3s are attached. But we're electronics people and can do that ourselves if needed.