Edit in JSFiddle

Result
JavaScript
CSS
HTML

$("a[href^='http']").each(function() {
    $(this).css({
        background: "url(http://favicon.qfor.info/f/" + this.href + ") left center no-repeat",
        "padding-left": "20px"
    });
});

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

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<a href=http://jsfiddle.net/chriscoyier/6Vg7t/3/>JSfiddle</a>
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