A friend sent me this pic and wants to know. I've never seen one.
From Andrew Scrivani via Twitter
Honestly, this reminds me of nothing so much as my mother's old knife sharpener. It had a few tightly spaced ridges, like on this gadget, and you ran a knife between the ridges to quickly sharpen it.
Readers, can you identify this gadget? Ever seen anything like it?
(Image: via Andrew Scrivani)