WS2812 LED are amazing! They are just like any RGB LED but are controlled through a single data line instead of 3 individual pins. You can specify any color of the rainbow as well as brightness. Keep in mind though that to use these, you will need a microcontroller such as an Arduino and a code library such as FASTLED.or the Adafruit NeoPixel Library
If you are looking for a great addressable LED in the more common LED form factor, then this is the perfect choice for you.