I got some nice WS2812s on a strand (PixelLights / ROK LED) from @mnielsen for this holiday season, and found that I wanted a fairly specific thing: I wanted to be able to emulate several classic kinds of Christmas light strand looks, as well as add variable amounts of twinkling.
Here’s the newest gen - you can get a sense of how they push into gutters:
I uploaded the pattern called “Twinkling Classic Xmas Strands” to the pattern library. It definitely looks best on a strand, and is a very different effect on a closely-spaced strip or matrix.