I came across this great chart a while ago, and saved the image to my computer. Regrettably, I can no longer find the website it came from, or I'd link to it.
[later....I've realized I shouldn't have this image in this thread without permission. Now that we know the site's address, here's a link to this great color chart image!]
Description of chart: Samples were made by using Kool Aid and Flavor Aid (FA) to dye the yarn! The left column appears to be dyed on white wool, while the right column is the same color dyed on a natural grey wool.