They are a novelty and hobby for me. I usually have extra space in veg for a plant or two. I have thrown them in the corner of my flower room, less yield but still better than empty space.
If your interested in some to play with, I would be happy to send you some.
Maybe, or Metallic Mascara remember I'm trying to shorten the name.
I though of calling it Eyebrows but that may be over the head of most here. You see a lot of the Hispanic women here shave off their eyebrows, then re-draw them on. Usually they look very fake and surprised.