I remember reading about the Blue LED when it first started to appear. It was interesting reading what they thought how it would be used at the time with being able to do true R/G/B the thing everyone was talking about. Not sure how much later before they were used for shiny round discs but it wasn't part of the article's prognostications. This is all a bit nostalgic as I read about that in a printed magazine when those were still a thing.