Shots of electric blue have been all over the fall runways, and beauty trends are following suit. Most famously, Marc Jacobs dyed his models’ hair blue, adding a punkish twist to an otherwise entirely sophisticated collection. Duckie Brown added turquoise overtones to the moppy-haired models of his men's collection. And Jovovich-Hawk applied shocking blue around the eyes. Just be sure to use in moderation, in order to avoid Smurfette comparisons.