Order of H'Pak

I'm not a Doctor Who fanatic by any means, but I found this article from Wikipedia on The Missing Doctor Who Episodes fascinating, from both a sci-fi fan and media archivist perspective. Amazing to me that the BBC simply destroyed all copies of the originals of these episodes as normal business practice.

Any Doctor Who fans out there heard of these before?

Fan of the Tom Baker era Doctor Who in all it's cheesy sci-fi glory, but don't really keep up with the lore and history so hadn't heard of this.

trivia: One of Dr. Who's travelling companions from that era now has her own show on the BBC - playing an older version of the character she played on the Dr. Who show. 20+ years after she left Dr. Who. How's THAT for a delayed spin-off?

http://www.scifi.com/sarahjaneadventures/