jccq writes "Both Google and Yahoo have been supporting Semantic Web markup (RDFa, RDF and Microformats) for weeks and months respectively. What they do, at the moment, is use the markup only for visual feedback by returning better looking, more functional 'page snippets.' But how would it look if you could get all these bits and compose them automatically to form a single structured information page about what you're searching for? The folks at the DERI institute have just released Sig.ma, a visual browser and mashup generator that will go all over the web of data and find dozens of sources to combine together when answering a user query. It also comes in API mode to reuse the information Sig.ma finds inside applications. Here are a screencast and a blog post, with semantic-web-geek details."