Brains6277 [creativecommons license] via Wikimedia CommonsAs anyone who has unwittingly walked into a web can attest, spider silk is among the strongest yet stretchiest fibers known. Standardized by weight, it is five times stronger than piano wire. Its exceptional mechanical properties make spider silk of great interest in materials science. Yet our understanding of these characteristics is limited because the methods available to measure them tend to be invasive and destructive.