$(document).ready(function(){
	
	//Hide div w/id extra
   $("#extra").css("display","none");

	// Add onclick handler to checkbox w/id checkme
   $("#checkme").click(function(){
	
	// If checked
	if ($("#checkme").is(":checked"))
	{
		//show the hidden div
		$("#extra").show("fast");
	}
	else
	{	   
		//otherwise, hide it 
		$("#extra").hide("fast");
	}
  });

	});