I have a $121 pending order at DiscountYarnSale.com. I keep thinking, "but this is madness! I don't even have plans for some of that yarn!" But they are gorgeous yarns and good prices and I do think I'll use every scrap.
And I'm starting to get, really get, why folks have good-sized stashes. Because once you start accumulating good yarn, man!, it must be fantastic just to look over your cache of really nice yarn and think of the possibilities and really feel... lucky.