RLC is a tool that performs reciprocal link checking automatically. Simply tell it where the remote Web pages you wish to monitor are, and the URLs of your links. It will then crawl the remote Web pages and give you feedback on the latest status (found, link not found, or page not found/network error). You may activate the checking as needed, or set up cron to carry out the checking once a week or so.
The Copy URL+ extension for Firefox and Mozilla makes it possible to copy the current document's address to the clipboard along with additional information such as the document's title, the current selection, or both. This behavior could be useful when you want to send an interesting link to a friend by IM or email and out of laziness don't want to copy the parts individually.