test.html

<div id='div' contenteditable='true' onpaste='handlepaste(this, event)'>Paste</div>
<script>
function handlepaste (elem, e) {
    var savedcontent = elem.innerHTML;
    if (e && e.clipboardData && e.clipboardData.getData) {// Webkit - get data from clipboard, put into editdiv, cleanup, then cancel event
        if (/text\/html/.test(e.clipboardData.types)) {
            elem.innerHTML = e.clipboardData.getData('text/html');
        }
        else if (/text\/plain/.test(e.clipboardData.types)) {
            elem.innerHTML = e.clipboardData.getData('text/plain');
        }
        else {
            elem.innerHTML = "";
        }
        waitforpastedata(elem, savedcontent);
        if (e.preventDefault) {
                e.stopPropagation();
                e.preventDefault();
        }
        return false;
    }
    else {// Everything else - empty editdiv and allow browser to paste content into it, then cleanup
        elem.innerHTML = "";
        waitforpastedata(elem, savedcontent);
        return true;
    }
}

function waitforpastedata (elem, savedcontent) {
    if (elem.childNodes && elem.childNodes.length > 0) {
        processpaste(elem, savedcontent);
    }
    else {
        that = {
            e: elem,
            s: savedcontent
        }
        that.callself = function () {
            waitforpastedata(that.e, that.s)
        }
        setTimeout(that.callself,20);
    }
}

function processpaste (elem, savedcontent) {
    pasteddata = elem.innerHTML;
    //^^Alternatively loop through dom (elem.childNodes or elem.getElementsByTagName) here

    elem.innerHTML = savedcontent;

    // Do whatever with gathered data;
    alert(pasteddata);
}
</script>