This is my favorite yarn shop in Boston! It's deceptively small- tucked into a building in Brookline Village near the T stop- but it's full of almost any yarn you could be looking for (brand, color, and gauge). They also sell books, buttons, patterns and needles, hand-dyed silk ribbon, etc. The sales staff are helpful, the prices are reasonable (not cheap, but everything is high quality) and they even accept returns. I think they offer knitting classes, but I've never been to one.
Pros: amazing selection, cozy ambiance, nice staff
Cons: none to speak of
more