The Revel has a sink drain switch (macerator) for the galley. However to use the sink you need to turn on the water pump. The button for this is around the corner on the One Place panel. Unfortunately this control is software driven and there is a slight delay while the One Place determines the current state of the pump (to display either On or Off). This gets to be a pain. Fortunately, WB added a solid-state water pump control relay to the pump operation which we can piggy back on to add another remote switch and state indication light. Plus you retain the macerator function too! The FB Revel site has many versions of this - it's where I got the idea.
I added 4 wires (2 for the light and 2 for the pump control), and ordered a custom switch from Rockerswitchpros.com. This is a momentary switch in both positions with an LED as well, part number VLD1-AX0B.
This the wiring diagram (stolen from the FB Revel Group):
Just to document my connections:
Pin Description (as appears in diagram above)
The water pump control is below the Nautilus control panel behind the black louvered cover plate (a pretty poor location for an electrical component - bound to get wet when you service the filter or spring a leak...).
My first attempt to mount the switch was to reuse the original bezel by cutting out the center section. That worked, but held the switch out from the cabinet by an extra 1/2" and not very securely. That led to it potentially snagging on clothing or being hit accidentally or getting ripped out. I was going to order a custom labelled switch for the pump anyway, so I decided to replace the unlabeled "mystery" switch above the fridge (its for the running board lights) as well with labels! Turns out the running board light switch uses a simple flush metal bezel, exactly what I wanted- which I was able to find on the WB parts list - part number 144363-02-CHT. So I ordered one. It's a much better solution in my opinion.