Just found another source for incredibly inexpensive yarn: Catnip Yarns.
Most of it is undyed, too, so it would be totally ready for dyeing experiments. Sock yarn is the Kona Superwash Fingering, 1120 yards for $10.99, or the Treadsoft Superwash, 980 yards for 12.65. I also think I'm in love with the chocolate alpaca, which would be a nice cozy sweater.
Still working on my next pair of cashmere socks — the pink and purple ones this time. Turned the heel this morning, so I should be done sometime this weekend.
Plus I got into Sock Madness, so there are some funky socks in my future.