Knowing how long it takes for your pages to load and what browser and platform your customers are using can be very helpfull...
<SCRIPT LANGUAGE="JavaScript"> <!-- Begin var startTime = new Date(); startTime = startTime.getTime(); function doneLoading() { var stopTime = new Date(); stopTime = stopTime.getTime(); document.form1.LOADING_TIME.value = ((stopTime - startTime) / 1000) + " seconds"; document.form1.PAGE.value = document.title; document.form1.SUBMITTER.click(); } function checkForDuplicate() { if (document.form1) { document.form1.REFERRER.value = document.referrer; document.form1.PLATFORM.value = navigator.appName + " " + navigator.appVersion; return true; } else { return false; } } // End --> </script> <BODY onLoad="doneLoading()" bgcolor="#00FF00"> <SCRIPT LANGUAGE="JavaScript"> <!-- var now = new Date(); // --> </SCRIPT> <FORM name="form1" METHOD=post action=" " onSubmit="return checkForDuplicate()"> <input type="hidden" name="PAGE" value="none"> <input type="hidden" name="LOADING_TIME" value="none"> <input type="hidden" name="REFERRER" value="none"> <input type="hidden" name="PLATFORM" value="none"> <input type="submit" name="SUBMITTER" value="Ok"> </form>