I visited Melbourne a few months ago, and there were quite a few of these near the CBD (though not all of them, which might explain why you haven't seen them).

I visited Melbourne a few months ago, and there were quite a few of these near the CBD (though not all of them, which might explain why you haven't seen them). They look like a regular crossing button, but the button part is painted black and has a red V made from LEDs (IIRC).