Edit in JSFiddle

$("#foo").click(function () {
    alert('click event, will change the link');
    this.href = "http://bit.ly/lying-links";

    // optional: set the link back so it keeps working
    setTimeout(function () {
        this.href = "http://www.google.com"
    }, 100);
});

<h2>href changing</h2>
<p><a id="foo" href="http://www.google.com">link to google.com</a></p>
<p>Hover over the link and watch the status bar. It should say http://www.google.com, but if you click the link you'll be sent somewhere else.</p>