268 Medium Lilac / Dark Purple
BrickLink: Dark Purple
Introduced in 2004 in full force -- Knights Kingdom II, HP Knight Bus, Duplo, and Belville. This color was very variable for a while, which was especially noticeable in the all-purple Knight Bus. This has since been fixed, and it remains a very common color. The front two parts in the photo are often found in Pick-a-Brick walls.