The Magnus Archives: British horror/mystery anthology with a fantastic meta plot and tons of connections between episodes.
Rusty Quill Gaming: An actual play Pathfinder podcast by the same folks making Magnus. Showcases a bunch of other tabletop systems too from time to time.
Potterless: A 20-something-year old guy reading the Harry Potter books for the first time, commenting on them chapter by chapter and always having a fan or two in as guests to explain/debate.
Archive 81: Horror/scifi. Super weird but pretty well made. Especially the third season is really great.
On the topic of Tanis and The Black Tapes: I will honestly not recommend them. There's over 30 hours of Tanis so far and I can't really say what it's about without explaining far too much. And TBT is, so far at least, ending in the worst way possible. As in it's right out terrible writing and a lazy excuse for just ending the series. If anything I guess listening to both can be recommended if you're in doubt about what not to do when making a story.
To see a world in a grain of sand, and a heaven in a wild flower.
Hold infinity in the palm of your hand, and eternity in an hour.
William Blake - Auguries of Innocence, line 1 to 4