One of the things I love about Firefox is the immense range of extensions that can be added to the basic browser (I have 72 and counting) Some are purely for fun, some hum quietly to themselves until you need them,but others are invaluable, to the point I'd lost without them. The latest in my must-haves is CoolIris. Once installed, it places a little Blue box by any links you hover over. Placing the Cursor on the box brings up a pop-up Preview of the page linked to, usually quicker than actually clicking on the link. Move the cursor off the preview and it disappears. If you want, you can navigate through the preview like a normal page, or lock the page open if you want to move the cursor away. This previewing is a real time saver if you have an number of links to go through, such as a search engine page (though for Google there is another extension that puts thumbnails on the search page) or a listings page or any page you're just curious about, without having to open and close an number of tabs.