In JavaScript, Strings are their own object. As such, they have their own set of methods you can use to manipulate their attributes. This can be much faster than inserting the entire HTML markup.
<html>
<body>
<script type="text/javascript">
var sent="I should blink.";
document.write("Original Sentence: "+sent);
document.write("<br />");
document.write("blink, which doesn't work in IE "+sent.fontcolor("orange").blink());
document.write("<br />");
document.write("toLowerCase() "+sent.fontcolor("green").toLowerCase());
document.write("<br />");
document.write("toUpperCase() "+sent.fontcolor("red").toUpperCase());
document.write("<br />");
document.write("toLowerCase() "+sent.fontcolor("green").toLowerCase());
document.write("<br />");
document.write("big() "+sent.big());
document.write("<br />");
document.write("small() "+sent.fontcolor("red").small());
document.write("<br />");
document.write("bold() "+sent.bold());
document.write("<br />");
document.write("italics() "+sent.fontcolor("green").italics());
document.write("<br />");
document.write("fixed() "+sent.fontcolor("brown").fixed());
document.write("<br />");
document.write("fontsize(5) "+sent.fontcolor("green").fontsize(5));
document.write("<br />");
document.write('indexOf("h") '+sent.fontcolor("green").indexOf("h"));
document.write("<br />");
document.write('lastIndexOf("l") '+sent.fontcolor("green").lastIndexOf("l"));
document.write("<br />");
document.write("Superscript--sup() "+sent.fontcolor("green").sup());
document.write("<br />");
document.write("Subscript--sub() "+sent.fontcolor("green").sub());
document.write("<br />");
document.write("strike() "+sent.fontcolor("red").strike());
var lin="www.heroscapers.com";
document.write("<br />");
document.write("link() "+lin.fontcolor("green").link("http://www.heroscapers.com"));
</script>
</body>
</html>
This will produce the following output: