URL Tooltip is a simple add-on that performs a simple function. It shows a pop-up tool tip with the URL of whatever Web site link you're hovering over. You can set the font size, and toggle wrapping long URLs. That's it.
But by putting the power of URL preview into your mouse, you can then hide your Status Bar. Assuming you don't use it for anything else, this can save valuable screen real estate--especially in Netbooks.
URL Tooltip is a one-shot wonder, but that doesn't mean it's not a handy tool to have.