The first being Operator, a firefox extension that helps with the use of microformats, including things such as exporting hcard contacts. It now boasts support for RDFa and eRDF and has changed its description to be more about the use of semantic data, rather then just microformats.

The second is Zotero, another Firefox extension which is focused on collecting information for research and the like. New features includes the ability to index the PDF’s collected and better Word integration. The first couple times I’ve used Zotero it didn’t work at all, scraping-wise. The new version seems to work much better.