I've included a few links here, results of a search I made today for one of the ladies, to give you an idea of the current prices, as well as the many styles.
The balls that come off of these winders are very neat. You can stack them so easily in your containers. You can even tuck one in a purse, with a hook, if you turn it on its side.
Most of the winders that are in my very-low price range produce 4-oz balls. There are winders that will give much larger balls.
Aside from their stackability, there is another benefit to making these balls. I absolutely hate to be making time, on a roll, in a project, and suddenly have to deal with a clump of tangled yarn that pops up out of the center of a pull-skein. It slows everything down. It aggravates me. It cuts down on my crocheting pleasure. With these winders, I can do all my winding at one time. At that time, I expect the tangles. I am ready to deal with them. It doesn't slow down a work-in-progress.
I should mention that you clamp these on a table, to anchor them. Even a very strong tray table will work.
The only drawback is that the 4 oz balls means that you need to attach a new ball several times in a large project. This doesn't bother me in most projects, because I expect to attach it. It's a lot easier on my nerves than when I'm working for an 8 oz skein that I assume to be all one strand, and suddenly I find a knot in it - that drives me crazy.
I have not used all the links I'm listing, so please do not think of this as a recommendation. I'm only listing them so that you can see the photos of the various styles.
Herrschners has one for $45
Walmart has a cheaper one which looks just the same as mine, for about $31, online
Knitting Warehouse has the one I have and it's only $23
This is their "main" yarn winder page, but the one above is what I use, and the least expensive, to boot
Wow, this one's only $20
For fun, look at this one - this gal's boyfriend made her one from Lego's!!!!!!!