Vertical Labret Piercing
The vertical labret piercing's lower bead sits roughly where a normal labret would (just below the lip), but instead of passing straight through to the inside of the mouth, it travels at an upward angle, with the upper exit being on the top or even slightly forward on the lower lip. The end result is that both beads are visible. Normal jewelry is a curved barbell.
As a point of trivia, this piercing initially came to be popularized by error and mistaken identity. In 1995, a photo was sent to BME labeled "vertical labret" — it seemed to be a new type of piercing, so a section made a section for it and it was added. As with all new sections, suddenly more photos started coming in as people emulated it. Not long after the piercing became part of the common language, and now is a very popular piercing, more commonly among women.
Shannon Larratt, editor of BME, writes: "Later I found out that the person who'd sent in that first picture had simply gone to an inexperienced piercer who'd tried to do a labret but failed in the placement; she'd labeled it "vertical labret" to hide the mistake."