Abstract. Annotations support understanding, interpretation, sensemaking and scannability. As valuable as in paper-based contexts, digital online annotations provide several benefits for annotators and collaborators. To further explore the real benefits of online annotations, we implemented a simple Web Annotation tool, SpreadCrumbs, to support our studies. The tool provides a simple annotation mechanism, simulating real-world paper-based annotations. In addition, the tool supports search, sharing capabilities and social navigation. We conducted a series of user studies that empirically demonstrates the benefits of "in-context" annotations for refinding and sharing.