Something

function ajaxFunction()
{
	var ajaxRequest;
	var rand = parseInt(Math.random()*100000, 0);
	
	try
	{
		ajaxRequest = new XMLHttpRequest();
	}
	catch (e)
	{
		try
		{
			ajaxRequest = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch (e) 
		{
			try
			{
				ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch (e)
			{
				alert("Your browser broke!");
				return false;
			}
		}
	}
	
	ajaxRequest.onreadystatechange = function()
	{
		elem = document.getElementById('time');
		
		if(ajaxRequest.readyState == 4)
		{
			elem.innerHTML = ajaxRequest.responseText;
		}
	}
	
	ajaxRequest.open("GET", "serverTime.php?rand=" + rand, true);
	ajaxRequest.send(null);
}