What are you doing with html, xhtml, xml, etc

I'm doing a session on building an xhtml/xml framework for course development.
I'm curious as to how you all currently use html, xhtml, xml, etc. Sometimes it almost seems as if people think that everything is going to Flash - but Markup Languages are of course still kicking strong and growing so I wanted to just get a feal for the types of things you're all doing with MLs. Are you just making static html pages, or using some xml? A little or a lot?