I've been watching a YouTube channel called Noclip since it's launch, about 6 years ago, and their video game documentaries are really impressive. If you've never heard of them then I highly recommend you check out the Half-Life and CD Projekt videos. It was founded by Danny O'Dwyer, who was widely known before Noclip as a host and video producer at Gamespot.
Recently though, they came into possession of thousands of video tapes containing video game media spanning the late 1990s to 2010, such as E3 conferences, game trailers, and footage of early game releases, most which had not previously been available on YouTube or anywhere else and are slowly going through the process of digitising them all.
A few days ago now they uploaded a video of what they've found so far and if you even have a passing interest in video game history, you should give it a look.