my sister just bought me OPI black shatter from the katy perry collection. i've heard of it before but never seen it on anyone except in pictures. i put it over top a hot pink color i already had on, and now i'm going to have the urge every time i put on my nail polish to add the shatter. it's used as a black top coat, that shatters as it dries. very cool stuff! i guess shatter comes in a variety of colors, but black is definitely a favorite.