I've been using a product line for a while that I'd like to share with you, because time and time again they are a real solution provider.
Simply Automated is a manufacturer of Universal Powerline Bus (UPB) devices. They have a well developed line of products for this category and I find myself using their products on more and more installations. UPB is a great retrofit approach to lighting control and additions. A controller switch can be located anywhere that there is power, whether it is an existing wall switch or even just an outlet.
On a recent lighting project, my customer requested that 3 lights on 2 separate buildings be controlled from one switch location. To further complicate this request, she asked that each light be individually switchable independent of the others. Without batting an eye I knew instantly how do do this and I was excited that she suggested it. In fact, in the overall scope of installation I think her request actually simplified the project!
The lighting project is the addition of 2 new 20 watt LED down lights from RAB lighting in my client's newly paved back patio area. One of the fixtures was mounted on the back of the house, the other on the side of the detached garage. She wanted to be able to control these new fixtures independent from her existing decorative porch light, but at the same switch location.
By replacing the switch to her porch light with an SAI universal dimmer controller, I now have the command switch for the project. That switch controls the local fixture load, and can send commands to the Relay Fixture Modules installed into each of the new fixture's electrical back box. To guarantee that there are no "call backs" on the installation, I put a phase coupler in the main electrical panel to ensure that the modules all talk to each other reliably.
I installed a "Single-Rocker 4-Button Oval" faceplate on the controller switch.

The half-size rocker intuitively controls the local porch light, while the 4 individual buttons are programmed to control the 2 new fixtures and 2 "scenes" that I programed based on how she wants to use the space. One scene is for quiet enjoyment of the new outdoor space while the other scene is fully lit for nighttime company.
A secondary control switch, located outside will be added in the future. This is where SAI has simplified the project for me. I don't have to run new wiring all over the attic or back and forth to the garage or the switch. UPB utilizes the existing power wires of the home and new switches can be added anywhere there is power in the home. With over a dozen faceplate types in six color options, any switch can be reconfigured for future additions in lighting control.
What I really enjoyed about this project was how a product line that I use to get around challenging situations has turned into a feature of my installations. Sometimes I think I take for granted some of these wonderful tools I have in my bag of tricks, and it was nice to highlight Simply Automated's contribution in this installation.