Not many solutions to moth holes have inspired fan pages on Facebook. But Woolfiller provides a surprisingly easy solution to the age-old problem of holey sweaters. Take the special wool and felting needle and poke the needle — which has small hooks along the point — through the wool and your moth-eaten garment. The repeated action binds the fibers together, making a felt patch on your cardigan, sock or rug. Heleen Klopper of the Netherlands created Woolfiller as part of an interactive museum exhibition on sustainability, and so many visitors wanted to buy it that she started making kits. Klopper has come to see moths as design collaborators. Their damage is her opportunity to add a twist — a red square, say, on a blue turtleneck. "When something is broken," says Klopper, "people dare to do new things." Moths, eat your hearts out.