The Stack Exchange communities could really do with incorporating RDFa into its platforms.
It would provide a way to share and aggregate questions and answers across platforms. Could be achieved by producing a lightweight domain specific ontology (QA vocabulary) and then allowing additional snippets to be added to enrich text (folksonomic vocabulary - already an ontology for tagging) and link to other things on the web (not just a hyperlink, but predicatively described). The lightweight domain specific ontology could also be adopted by non-overflow QA forums, facilitating the syndication of QA forums across the World Wide Web.
Has anyone looked into this? It wouldn't require any business change and requires little effort to accomplish this.