She was trying to hang a banner, and the hammer came down from its perch on top of the ladder. I'm not sure what speed it was going when it finally impacted her face, but it made a nice sickle-shaped scar. Which is appropriate, really, given a) the implement that did it; and b)the fact that she works for a labor union.
She is fine, by the way. She's got a couple of stitches in her forehead, but she'll be fine if she just keeps taking the ibuprofen.