Update 2009-07-24: The original author of CopyURL+ has not updated it for several years; instead, see CopyURL+ by Marbux for a more up-to-date release.
Recently I’ve discovered CopyURL+, a handy Firefox extension that makes it easy to copy web page URLs and titles for citation in your blog (or elsewhere). From the project homepage:
The Copy URL+ extension enables you to copy to the clipboard the current document’s address along with additional information such as the document’s title, the current selection or both.
You might find this behavior useful when you want to send (IM, email) an interesting link to a friend and out of laziness convenience you don’t want to copy the link and an explanation of what the link is in a single step. The explanation can be as short as the document’s title or it can be a descriptive text from the document.
The real power in CopyURL+ is the customization they provide, allowing you to create links in the format that you need. Customization is pretty easy (once you find the right spot for your user.js file). I’ve added entries for Markdown (my text filter of choice for MovableType) and Wiki (for my Twiki editing at work):
user_pref('copyurlplus.menus.1.label', 'Copy Markdown link');
user_pref('copyurlplus.menus.1.copy', '[url]: %URL% "%TITLE%"');
user_pref('copyurlplus.menus.2.label', 'Copy URL + Title (Wiki)');
user_pref('copyurlplus.menus.2.copy', '[[%URL% %TITLE%]]');
Now, what would really be handy is a merge of this with Linky. I’d love to be able to open several web pages in Firefox and with one command have links to all of them ready for my blog post.
The latest tweets from 
This was great advice, thanks for writing it up. This was my very happy result:
user_pref('copyurlplus.menus.1.label', 'Copy Linked Text');
user_pref('copyurlplus.menus.1.copy', '<'a href="%RLINK%">%TITLE%</a>');