How to convert characters to HEX equivalents

[geuis]

I would like to be able to input any character and convert it to its hex equivalent. Are there any existing scripts that will do this or how can I write my own?

[Charles]

<script type="text/javascript">
<!--
String.prototype.toHex = function () {return this.charCodeAt(0).toString(16)}

alert('a'.toHex())
// -->
</script>