Over at Male Pattern Boldness, Peter Lappin shows how he turned a thrifted silk tie into a D-ring belt. Grosgrain ribbon interfacing works as interfacing, stabilizing the bias silk so it can be worn as a belt. (Without interfacing, the long tube of bias fabric would stretch out of shape.) He shows it for menswear, but I think this would work equally well for women. Go to his tutorial to see how he made it.
[photo from Male Pattern Boldness]
By Anne Weaver