The document discusses opportunities to improve the functionality and user experience of online public access catalogs (OPACs) through the adoption of Web 2.0 principles and features. It summarizes surveys that found users find existing OPACs difficult to use and lacking modern features. It then describes experiments at the University of Huddersfield to enhance their OPAC with spell checking, keyword suggestions, borrowing recommendations, and user reviews. The document advocates for an "OPAC 2.0" that better exposes library data through open web standards and embraces serendipity, user participation, and integration with external sources like Wikipedia.