This subject has been very interesting reading. And I do want to add my best find.
In summer of 2000 I went to a flea market and found a bag of fabrics. I asked the vendor if I could take it out of the bag to sort it. Needless to say that was not a good idea. He told me to take the whole thing for $5. It was a black garbage bag and stuffed so tight I staggered to my car and dropped it on the ground so I could get my keys out of my pocket to open the trunk. I washed and ironed for several days and and found nearly all was suitable for quilting. I quit counting when I had measured 50 yards of fabric. That was when I first decided to make quilts, and have been doing quilts ever since.
That was probably my once in a lifetime good fortune find.