I haven't seen any complaints about the Elmer's Ultra Clean Washable *Markers*. They seem to wash out of fabrics just fine. Here is a link to them on Amazon, although I have seen them at Walmart too:
http://www.amazon.com/Crayola-Ultrac...dp/B003HGGPLW/
Edit: Just wondering. Elmer's also makes Ultra Clean Washable Crayons. But why would a quilter prefer using crayons over markers?