// getComputedStyle wrapper

function getStyle(element, styleProp) {

  return element.currentStyle ? element.currentStyle[styleProp] :

      getComputedStyle(element, null).getPropertyValue(styleProp);

}

​

// cheesy convenience function

function textDiv(textContent, className) {

  var tmp = document.createElement('div');

  if (className) tmp.className = className;

  tmp.appendChild(document.createTextNode(textContent));

  return tmp;

}

​

var box = document.getElementById('box'),

    glyph = box.appendChild(textDiv('g', 'glyph')),

    size=500;

  glyph.style.position = 'absolute';

  document.getElementById('status').appendChild(

  textDiv('Initial computed width: ' + getStyle(glyph, 'width'))

);

while (parseInt(getStyle(glyph, 'width'), 10) <  100) {

  glyph.style.fontSize = size++ + '%';

}