I'll likely be using XSLT and possibly XSL-FO in my Blogger backup utility, so this caught my eye (since I have little practical experience using XSLT and none with XSL-FO).
What I like about this site is that it's not just a link site but a reference site.
David Pawson (author of XSL-FO Making XML Look Good in Print) has put together this nice reference site, based on tasked based questions and answers.
"1. How to use HTML as input documents? 2. Embedding HTML in XML documents using HTML dtd 3. HTML to XML conversion ... 5. How to embed HTML in XML 6. Including BR in an XSL template
10. HTML in XML
13. Parsing HTML as XML
That's just a tiny bit of the information available...