I recommend downloading the video instead of trying to watch in a
browser; it's 150MB and 20 mins long but well worth watching.
(I have included urn:sha1: URIs in various posts here in the
past, but most of them were bogus, oops. I just wrote a little
script [1] to generate good ones.)
Hmm... urn:sha1: doesn't seem to be on IANA's list of URNs [2];
what's the recommended way to refer to files by their checksums
if not urn:sha1?