This is pretty exciting, as far as I'm concerned.
One of the things I've been checking YouTube for semiregularly, ever since I came to it, was An American Family. Considered the first reality program, AAF followed the family of William C. Loud for nine months in 1971 and wound up with 300 hours of footage, whittled down to twelve one-hour programs that aired in 1973. The Loud family (I know at least two bands named after them) came apart at the seams over the course of the show, which introduced the world to Lance Loud, one of the first openly gay people ever seen on television.
It's been hard to see since (confounded music rights); once again, God bless YouTube for giving it a forum, and many thanks to "subcin," the guy who posted it. I recommend watching the other excerpts posted as well.
This is the most famous scene of the series. Bill Loud's come home from a business trip, with no idea that his wife is about to let him know she wants a divorce.