Actually only twice that I can remember. one time I bought a white on white at Joann's. I think it was about 13 yards. I had a coupon for 50% off I think. I've used it up.
Sad. It was a nice color and I often wish I had more.
Then, the second time was more recently. I asked the local fabric shop to get me a whole bolt of their nice black cotton. The bolt was 30 meters!