All of the European style switches previously mentioned (that I could find info on) require an electrical box, i.e., cutting a hole in the cabinet. It's also very hard to find info on them or where they can be purchased.
I ordered one of the Skylink wireless switches to see what they look like in real life. Turns out the wireless switch/transmitter is the same depth as a standard Decora switch and switch plate. When mounted to the wall, there's no additional depth to the switch/transmitter, so from that perspective, it's exactly what I'm looking for.
I took it apart to see if it could be altered to be a simple dry contact switch. The "on/off switching" looks like it is being done by magnets. There's a small metal object that I assume is a magnet in the rocker that is directly over something (can't tell what it is) on the circuit board underneath the rocker. No physical contact is made between these two objects. When I push on the rocker to get it to change positions (press lightly on the top half), the transmitter's LED blinks (which I think means it is sending a signal). Whenever the top half of the rocker "moves away" from the circuit board (e.g., when pressing on the bottom half of the rocker), it blinks again. The important thing is that when pressing on the bottom half very slowly and controlling the rocker motion, it starts blinking very soon after the rocker starts moving, well before it gets to the bottom-half-in position. So it seems like the only motion that matters occurs at the top of the rocker, with regard to on/off switching.
There's actually two "press-types" for the switch. Pressing a bit harder and holding (even if it is already in the required position, e..g, "on") causes dimmer actions. There are a couple of momentary pushbutton microswitches on the circuit board, one under each half of the rocker (top and bottom). I verified that the rocker doesn't play any roll other than physically pushing down on the microswitches by removing the rocker and pressing the microswitches directly, and they did flash (and at a different rate than the on/off rate) the same as when pressed by the rocker.
Downsides:
- The receiver can't dim LED's, but I'm okay with that.
- Relies on battery. Might be okay if I can get a year or so per battery.
- I don't think there is any way to integrate it into an Elk M1G and/or CQC environment to give me more flexibility and greater control, which is a high priority for me in this whole-house remodel project. I plan on implementing UPB for a lot of lighting control, and this switch (the light it controls) is a prime candidate, e.g., be able to turn off all kitchen lights with a single "command". I don't think this would be possible if this switch/receiver is in the mix. Maybe if a UPB relay controlled the power to the receiver, something could be done, but I don't know enough about UPB (or this receiver) to know.
I have a receiver arriving on Monday, so I will be able to see what happens when power to the receiver is cut/restored.