Edit in JSFiddle

#element {
    color:orange;
}
#element {
    *color: white;    /* IE6+7, doesn't work in IE8/9 as IE7 */
}
#element {
    _color: red;     /* IE6 */
}
#element {
    color: green\0/IE8+9; /* IE8+9  */
}
:root #element { color:pink \0/IE9; }  /* IE9 */






/* irrelevant to the demo */
body{
    font-family:sans-serif;
    background:#000;
}
a{
    background:blue;
    color:#fff;
}

<div id="element">
    <ul>
        <li>IE6 should be red</li>
        <li>IE7 should be white</li>
        <li>IE8 should be green</li>
        <li>IE9 should be pink</li>
        <li>Everything else should be orange</li>
    </ul>
    <em>This is an example demonstrating the <a href="http://blog.vervestudios.co/blog/post/2011/05/13/IE9-Only-CSS-Hack.aspx">IE9 Only CSS Hack</a>.</em>
<pre>

 \0/
  |
 / \

</pre>
</div>