Status images

[alexgeek]

Hypothetically,

Say I want a status image on my site because it's in beta and I want to warn users when it's acting up.
Say the php goes like:

<?

$status="some mysql query which says yes or no"

if ($status == "okay") {
echo "<img src=\"okay.jpg\">"
} else {
echo "<img src=\"notokay.jph\">"
}

?>
that would be fine,
but they have to refresh the page to see if it's okay or not.
I'd want it instantaneous, is this possible with javascript or ajax?
You may say this is a lot of work for something so pointless, but this is just a simplified situation.