Edit in JSFiddle

$("a[href^='http']").each(function() {
    var domainname = $(this).attr('href').replace('http:\/\/', '');

    $(this).css({
        background: "url(http://www.google.com/s2/favicons?domain=" + domainname + ") left center no-repeat",
        "padding-left": "20px"
    });
});

a { display: block; text-decoration: none; padding: 5px; }

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