At Spoonflower (www.spoonflower.com), you can upload a design, and get digitally-printed yardage with your design printed on it! I only have about 114 designs sent to them so far, and have gotten some successful samples in light and medium colors. *
This is a design that started as a small dye-painted square of test fabric. Then I scanned it, Photoshopped it to get many colors, and made an array so it could print as yardage. Soon I'll order a sample to see how the colors come out. Then if that works well, I'll get a couple of yards to make perhaps a knee-length vest, lined in a teal fleece which I got for that, and then found it didn't go with the batiks I intended to use. And it will be my unique fabric.
Your designs remain private unless you choose to make them public, but no one except your self can buy them now. Someday. Unless one of your designs is chosen to be in the weekly contest, and it wins - in which case people can buy it for a week. And you would win some fabric. Right now they're printing on a quilting-weight cotton. Other fabrics later. (Update: several more fabrics now available, in different widths.)
This is a lot of fun. Click on the fabric to see some of my other designs.
*(Dark or black backgrounds with low-contrast images don't work well.)