The first Crayola crayons came out in 1903, and there were 8 colors: Black, Brown, Blue, Green, Orange, Red, Violet, and Yellow. Between 1949 and 1957, 48 colors were available. Then came the glory days of the 64-color box with built-in sharpener. Man, they got rid of Orange Red and Green Blue! You can see the history of the Crayola crayons, or see the 10 most popular colors. Blue came out on top, but my favorite, Periwinkle, is number 7.

An interesting bit of history: in 1999, the color Indian Red was renamed to Chestnut, because some teachers felt that children wrongly perceived the color to be representative of the skin color of Native Americans. But the crayon was actually named for a reddish-brown pigment found near India, "commonly used in fine art oil paint". (Link from metafilter)