"Max Headroom" television takeover - 20th anniversary

[mike@miscon.net]

So tonight marks the 20 anniversary of the video pirate (or hack)
of WTTW in Chicago; wherein someone dressed in a Max Headroom mask
overtook a Dr. Who episode, and replaced it with their own ramblings for
over a minute and a half.

You can find a brief description and
a clip here (watch the wrap):
http://gizmodo.com/gadgets/piracy-history/20-years-ago-tonight-max-headroom-the-video-pirate-took-over-chicagos-airwaves-325717.php

My question is: has anything like that (the complete overtaking of
an established radio or television signal) been done (or
attempted) here in Boston?

Mike