Ambient gadgetry: what’s this pylon doing in my neighborhood?

Not too long ago, this pylon appeared unheralded in my too-quaint neighborhood of tiny, turn-of-the-last-century brick and stucco houses in Boston. It’s not the Bunker Hill Monument. And it’s not one of those fake-authentic wrought-iron carriage posts, either. It’s electronic�but what is it?

It’s about twenty feet tall, sports what appears to be a microphone on top, and a couple of formidably-locked boxes are bolted at head level.

Is it an ambient sound monitor? Experimental telecommunications device? Beacon for the coming robot invasion? I’m posting my shoddy cameraphone shots here in hopes that some Gearfuse reader has an answer.