Well, I suppose it's not technically an Inktober piece, as it is just a product of the weekend and not something I set out to do for Inktober, but I figure it's ink and it's only one color, so it qualifies.
It's a tree with the pen I used to draw it: walnut ink with an Automatic 4A, on Arches Text Wove. The workshop was basically about how to create art without actually being artists, and also how to use our tools in novel ways. Yes, that's a very broad-edged pen that's about four times as wide as the tree that it drew, but it's what I used. The workshop was an absolute blast and I learned a lot, which I realized as I did my watercolor homework tonight - I understood what to do, how I could expand on it, and how to fix / cover up mistakes, and I wasn't afraid of my tools. I did what I needed to do in about a quarter of the time I would have taken to do the same thing last week because of what I learned over the weekend.
I'm rather proud of the tree. I was supposed to put leaves on it but ran out of time during the workshop, and I think I like it the way it is.