Cross browser method for detecting prefix.

prefix.js

(function(window){
  
  var styles = window.getComputedStyle(document.documentElement, '')
    , pre = (Array.prototype.slice
        .call(styles)
        .join('')
        .match(/-(moz|webkit|ms)-/) || (styles.OLink === '' && ['', 'o'])
      )[1]
    , dom = ('WebKit|Moz|MS|O').match(new RegExp('(' + pre + ')', 'i'))[1]
    , capitalize = function(str){ return str.charAt(0).toUpperCase() + str.substring(1) }
  ;//var

  if(pre)
    window.prefix = function(prop){ return pre + capitalize(prop) }
  else
    window.prefix = function(prop){ return prop }
 
  window.prefix.dom = dom;
  window.prefix.lowercase = pre;
  window.prefix.css = '-' + pre + '-';
  window.prefix.js = capitalize(pre);

})(window);