So yeah, this is a thing now.
People posting pictures of themselves balancing coins on their collar bone. The object is to see how many you can get balanced in row before the line falls. In theory, the more you get in a row, the thinner and more fit you are.
This totally bogus assessment of your over all health and fitness is brought to you by the fine social network that also gave us the belly button challenge. So take for what it is worth!