SO fiddle

Test Fiddle mainly for SO Questions

by Nick Craver

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.4/themes/overcast/jquery-ui.css">
<script type="text/javascript">
function SanitizeInput(input) {
    input = input.replace(/</g, "&lt;");
    input = input.replace(/>/g, "&gt;");
    return input;
}
document.write(SanitizeInput("Test!<marquee>bibble</marquee>"));
</script>