For some odd reason I could only buy these lights as a pair. They are a version of the very common "three LEDs and a dome" disco light sold cheaply on ebay, but rather unusually they are in a plastic frame designed to be mounted in a ceiling like a downlight.
The circuitry is the usual 3W power supply (spot-on 3W for both!) with three 1W LEDs in series (red, green and blue) and a little geared motor hooked across the circuit so it runs on the 8V across the LEDs. This version has a rather tacky twist to it though. A "flasher" circuit that detects loud noises and blinks the lights out briefly in a crude sound-to-light way.
The slightly jaw dropping way the sound to light is implemented is as a two wire module hooked right across the output of the little power supply module that simply SHORTS IT OUT when it hears a loud noise! This is why the lights blink out!
The little power supply is quite awesome in this regard, since it seems to be made of discrete components with a single diode rectifier, smoothing cap and then just a tiny scattering of components including two transistors (One surface mount and one TO92). The output is just the secondary winding, a diode and a small capacitor. Feedback appears to be through monitoring a feedback winding on the transformer. This gives surprisingly good current based control that see's the power drawn by the circuit drop according to the loads voltage and goes all the way down to about 0.3W when shorted out completely.