Firefox: If you're looking to reclaim screen real-estate from that not-so-tiny expanse of space the Firefox status bar takes up, don't let concern over missing URL mouseover information hold you back.
URL Tooltips is a simple Firefox add-on. Once you install it, whenever you place your mouse over a URL a tooltip bubble will pop up and show you the full URL. If your only reason for keeping the status bar around at the bottom of the screen is for checking URLs before clicking on them, you can disable the status bar and still enjoy that look-before-you-leap security.
URL Tooltip is free and works wherever Firefox does. Have a favourite URL-related add-on? Let's hear about it on the comments.