I was recently found out about the magic of drag and drop (hey, I was a fairly late switcher!). One of the more intriguing things I found was how drag and drop operates with links from a web page (at least when using Safari).
If you simply drag a link from a web page to an open text editor, it pastes the URL of the link to the open document. If you highlight the text around a link, including the link itself, then drag and drop it, you end up pasting the HTML coding used within that block of text (<a href...> tags and all), supposing of course, your text editor is capable of displaying HTML pages. This seemed to work with Microsoft Word and TextEdit, but not TextWrangler. For Text Wrangler, I simply got the text, but not embedded the embedded HTML tags. I guess this can be useful in copying portions of a web page.
This only seems to work with text-based links. If you drag and drop a graphic-based link, it simply copies the graphic, although doing this in TextWrangler brings up the URL for the link.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20050306133118651