jQuery.position()
by tkrotoff
HTML
<div>
<p id="el" style="margin-top: 30px">Text with 30px top margin</p>
</div>
jQuery.position(): <span id="jquery"></span>
<br>
offset: <span id="offset"></span>
JavaScript
var el = document.getElementById("el");
var position = $(el).position();
$("#jquery").text("left: " + position.left + ", top: " + position.top);
$("#offset").text("left: " + el.offsetLeft + ", top: " + el.offsetTop);