When HN users recommended it
1 HN user recommended this in 2014, in one comment.
20072026
Each tall tick is one HN user's first recommendation. A short tick is the same user again. Click a tick to jump to the comment.
1 HN user recommended this in 2014, in one comment.
Each tall tick is one HN user's first recommendation. A short tick is the same user again. Click a tick to jump to the comment.
Looks that way. Possibly it's essentially the same thing as this:
http://www.amazon.com/Jac-Zagoory-Beta-Inkless-Pen/dp/B005GL...
EDIT: Not quite. Apparently the tip of that pen is lead, while the one in this post is some kind of alloy. Same idea, though, I imagine: soft metal that rubs off much like a pencil.