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.
So after adding 4 wires (2 for the light and 2 for the pump control), ordering a custom switch from Rockerswitchpros.com and ordering a replacement bezel from WB (part 144363-02-CHT), we're in business. This is momentary switch in both positions with an LED too part number VLD1-AX0B.
This the wiring diagram - stolen from the FB Revel Group:
The water pump control is below the Nautilus control panel behind the black louvered cover plate (a strikeling poor location for an electrical component - bound to get wet when you service the filter or spring a leak...)
My first attempt to mount it was to reuse the original bezel by cutting out the center section. That worked OK, but held the switch out from the cabinet by an extra 1/2" and kinda loosely. That led to it potentially snagging on clothing or being hit accidentally. Since I was going to order a custom labelled switch for this anyway, I decided to replace the unlabeled mystery switch above the fridge (its for the running board lights) with a labeled one too. Low and behold, this switch uses a simple flush metal bezel - which I was able to find on the WB parts list. So I ordered one. It's a much better solution in my opinion.