These are seriously awesome, though.
The word yubinuki simply means "thimble" in Japanese. It can refer to the bucket thimbles we're accustomed to in the west, leather cuff thimbles, metal pad thimbles, or any one of several "thing that goes on your finger when you are sewing" accessories.
the above images are all yubinuki,and all blatantly stolen from the Internet
What we've specifically got here are kaga yubinuki (加賀指ぬき). They are padded fabric rings decorated with silk thread. The origin of this style of thimble is credited to the Kaga region of old Japan, modern day Ishikawa prefecture, hence the term kaga yubinuki. When the term "yubinuki" is used in English, it is almost always in reference to this unique type of embroidered thimble.
I discovered yubinuki by way of a related craft called temari (てまり), a topic upon which I really, really hope to do a tutorial soon. The two are related in that they both apply colorful geometric patterns of silk thread to a padded, curved surface. Yubinuki, however, are easier in my humble opinion: there are fewer divisions to keep track of, only one stitch to remember, and they are generally much smaller.
The materials to make a yubinuki are fantastically simple. You need only a small piece of fabric, a needle, some thread in a few colors, some strips of paper, and a little padding. The Japanese use loose-fiber silk padding, but for those stitching in the west, I find that a bit of an unrolled cotton ball works just as well. (Polyfil does NOT work very well, as it is very springy and hard to wrap around the ring base without bits of it sticking out everywhere.)
もし日本語が読めれば、こちらには簡単な how-to があります。:D
If you can read Japanese, here is a simple tutorial all on one page. A more complete tutorial and the pattern to make the double yabane (arrow-tail) pattern can be found here. Even if you don't read Japanese, it's worth a look at just the pictures in each tutorial -- you'll quickly get the feel for what is being done.
Yubinuki instructions in English are a little harder to come by. Fortunately, there is Chloe Patricia and her blog, Ma Mercerie. Madam Patricia gives excellent tutorials for building a thimble base, stitching, making and using patterns, and more, all in English. パツリシア様、大変お世話になりました！
Once you're comfortable with building a ring base, all you need to do is learn the knot to start a new thread on the ring:
...and the single stitch used to make all the various patterns:
What allows for the variety of patterns is the number of divisions you mark on the ring (how many zig-zags of each thread), and in what order the different colors of threads reach across each other. After you get used to the basic stitch, you'll likely be able to mentally de-construct a finished yubinuki and understand the pattern used to make it. I'll be posting the basic ones as I finish graphing them out. :D
Base-making tutorial: excellent pictures, Japanese text - also shows how to divide strips without measuring, using a line set or graph (from てんとう虫がやって来た)
Base and stitch tutorial: in Japanese (from Fujix Ltd. publishing)
Base and double yabane pattern tutorial: in Japanese, click each link in order from top to bottom to get a breakdown of materials, base making, divisions, stitch method, and pattern (from Thimble Japan)
From 茶飲み話: works from 2006, 2007, 2008, and 2009 (all separate links)
From Zuccaさん: handmade yubinuki gallery
From Quilt-Yui: handmade yubinuki divided by design type (click the various links beneath the words 店主のギャラリー, the fourth menu item down in the left-hand frame)
From 人鳥官: yubinuki and quilting, link goes directly to yubinuki section
Small pieces (category 加賀指ぬき)
Amerika tsukuri (full of yubinuki, temari, and miniatures of both)
...and there are a ton more. Try copy-pasting the Japanese term 加賀ゆびぬき (kaga yubinuki) into a GIS. Or, you know, just click here. :D
All actual pictures of kaga yubinuki in this post have been blatantly stolen from the Internet; I wanted to credit them, but I lost the links to the sites from which I saved them, 'cause I'm an idiot. -_-; すばらしい加賀指ぬきの写真は無断に盗まれてしまいました。もしかして、あなた様の写真がこちらに見つけて、おしえてください。大変申し訳ありません。
I'll be back soon with a step-by-step of some patterns~