Chickadee magazine claimed that carrots used to be purple. About.com lists other colors. Feel free to read it below.
Photo from about.com.

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•Red Carrots

Red carrots don't differ in taste much from orange carrots. Their red color, though, comes from lycopene, the heralded antioxidant in tomatoes.


• White or Golden Carrots

White or golden carrots are yellow or cream colored. They have a mild flavor with hardly any of the earthiness of other colors, and they're a bit sweeter than orange, red, or purple carrots"