Same deal with crochet hooks. I resented having to use a size G or H with some yarns; why couldn't I use a little one, like a D? (I had a slim dark green one of those too, at one point in my youth. What is it with slim dark green fiber-arts implements?)
It isn't just needles and hooks, either. I was fascinated with 22-count aida cloth for cross-stitching (that's 22 little holes to the inch), and when I was able to do a project on linen, with an even finer count? Joy!
(I should note, however, that the project on linen is sitting unfinished in my closet. Should get it out someday.)
I write on college-ruled notebook paper. I prefer 0.5 mm mechanical pencil leads to 0.7. I usually go with fine-point pens. I like slim wire hoop earrings and eensy metal studs. Back when I smoked, my preferred mainstream brand was Virginia Slims, especially the Superslims. My preferred Winamp skins are the ones that fold up into fully functional title-bar sized windowshades. (MMD3 and the default Winamp Modern are so choice.) I like tiny screen resolution on my computer. I dig super-slim CD/DVD and cassette cases.
But back to the craft implements:
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The nano-hook is a bit of a mystery to me. It used to belong to my uncle's grandmother ; it might be a 15 or so, and seems suited to crocheting sewing thread. There is no manufacturer or size information on it, but it's elegant and slim and I would cuddle it if it weren't so danged pointy.
Same goes for the 000, which came in a set of four sizes with five of each size. Its companions are 00, 0 and 1 and also just plain adorable. And now that I have sock yarn (tiny!), I can use them instead of admiring their shiny slimness.
The 17 and the Q? I'm something of a completist and couldn't resist likewise buying the largest hooks and needles I could find at the local General Crafts Store. I have since learned that there are S hooks, and 35 and 50 needles, but I think the compulsion to buy big has faded. Besides, if I ever have need of knitting, say, waterski tow line, I may be prepared with what I have.