RMB press on a link and choose Copy Link Location. This copies the url to the clipboard so you can then paste it into, say, an e-mail to a friend telling her about this wonderful new site.
The Menubar View->View Document Source or View->View Frame Source options load the source code for the page or frame into a text editor.
The little icon at the left of the Locationbar clears the Locationbar window when you LMB click on it. This can be very useful when you want to copy a URL from a text document such as an email, which you can do by simply;
Highlighting the URL by dragging the mouse pointer across it with LMB pressed. This is the standard Linux/Unix way of copying text.
LMB clicking on the icon to clear the location window.
Moving the cursor into the location window and MMB clicking to paste the URL there. This is the standard Linux/Unix way of doing a text paste.