Over the years I've done a lot of things with addressable rgb LEDs, mostly the APA102 (and clone; SK9822) series, and some commonly known 'NeoPixel' WS2812b stuff.
Most follow a similar design; they have a chain of the LEDs, hooked up to a microcontroller like an Arduino, or more commonly a WiFi enabled ESP8266 or ESP32 module. Depending on it's installation, it's then powered by USB, or LiPo cell(s) and a small LiPo charge module. Software-wise they run on FastLED, with an adaptation of the 100 line demoreel or fully custom effects.
very much a work-in-progress;
At the start of 35c3 I got a Decathlon non-electric kick scooter, to zoom around Leipzig and the congress halls. To really make it mine though, it needed LEDs! Shockingly, I didn't bring any myself, but was able to source a nice 5m roll of IP67 SK9822 from a fellow congress-goer. Someone from the HSNL assembly gave me a D1 Pro Mini and off I went soldering it all together and writing effects. Zip-tied my powerbank to the frame, and all was ready :) During the year, I patched it up, and redid the electronics a bit nicer, packaging it as a removable module with the LiPo's from an older powerbank, to take inside for charging.
So far done two lasercut dodecahedra, with embedded lighting. The first was from cheap wood, but with holes in the seams giving a very interesting lighting pattern around it.
The second was fully closed milky plexiglass, joining the edges by sewing them with more wire. The leds, microcontroller and LiPo cell make for nice even lighting (except on the bottom pannel), and I nicely hid the charging micro-usb in one of the edges.
Camping tower light
Came with boring white leds in the bottom, now houses a wooden beam with ledstrips on all four sides.
For my hackerspace I repurposed 13 boring white led fluorecent tubes, giving them the good rgb stuffs. They're all connected into a long chain with RJ45 sockets and cables, powered per 2 by a KOPPLA.