I subscribed to the Hedgehog Fibres Sock Club in August and have loved every skein so far. I'm not sure what I like more: the colors themselves or receiving two surprise skeins of yarn every month. Past Emily was taking care of Future Emily when she subscribed!
If you aren't familiar with Hedgehog Fibres, the yarn is hand-dyed in small quantities in Ireland. The fiber itself is so soft and perfect for socks and shawls (and probably sweaters too!). The colors are always so amazing and impressive; they glow on the fiber. Beatka has a keen eye for color and throws on speckles and random stripes with abandon, though it always works out and looks beautiful. I'm in love with every skein.
I purchased Cabaret and Pheasant from the Loopy Ewe earlier this year and have yet to use them. They look like the parents to lovechild Splash, which was one of October's club colors. They're all girly without being saccharine, which is something I can appreciate.
I plan on subscribing again when it opens next month. I just really like yarn clubs from my favorite dyers. It's so fun getting a surprise in the mail, especially when it arrives on a hard day or a day when you weren't expecting a present. I think it's a genius idea. I've toyed with this plan for Honeycomb Yarns too, but I'm still working out some of the kinks. But who doesn't like yarn?