I have been a light Emacs user for a few years now. I was so thrilled about discovering Org-Mode through an HN post [1], I went out looking for other cool Emacs hacks and found this Stackoveflow thread that has a number of them. Generally, I wouldn't link to a Stackoverflow question but this one has a number of great tips.
[1] http://news.ycombinator.com/item?id=651459