// Sample: <input type="text" id="email" value="Your Email" onclick="ClearInput('Your Email', this.id);" />
// Include in HEAD: <script type="text/javascript" src="/incfiles/ClearInput.js"></script>
function ClearInput(value, id)
{
	var input = document.getElementById(id); // Gets the input field based on its id.
	if (value == input.value)
	{
		input.value = '';
	}
}