I stumbled upon this awesome new place to get designer upholstery fabric! Modern Fabrics "reclaims and collects new fabrics from the finest luxury furniture companies throughout the United States and offers them to you at 50-75% off list price." They are also "committed to building a larger market for these discarded fabrics while ensuring an ecological textile life-cycle. We want to encourage designers to utilize existing sources of textiles before resorting to consuming more raw materials."
While still not maybe cheap enough to do a large piece for me - the prices would be great for chair seats and other smaller projects.
I also want to share a great post by Annelise of quarterlife lifestyle (go Boston bloggers!) about where to buy fabric in Boston. A few on the list were new to me!