I uploaded a photo of something I got at a used building materials warehouse so they didn't know what it was called either. Please take a look at my album to see it.
Really want to know what this is called, just in case I want to buy more. It's 3/8" plywood with a hardwood veneer, cut into parallel, beveled strips and cloth-backed so it can be curved in either direction. The piece I bought was 36" x 8' but I don't think it was a full "sheet".