One really cool one is the references to the novel/movie - The Shining by Stephen King.
In Fallout 76, there is the Torrance House (The Forest Region), named after the Torrence family (Jack, Wendy and their son Danny). Most of the Torrence House is not accessible (or I didn't find a way in!), but it does have that haunted gloomy feel you'd expect. The photos are from two separate days, one was sunny, and when I went back in was raining.
There is scaffolding around it that offers access to the second floor and balconies and if you have a jetpack or marsupial you can access the roof. I didn't try just climbing up there, but there may be a way to jump up.
On the lovely verdigris copper roof, found this couple with the blocks spelling out Hubba Hubba. I'm not sure if this is reference to the ghost that was messing with Jack or some other Shining reference or could be totally unrelated. (It does have the requisite Teddy Bear!).
From the roof I was able to take an overview photo of the Torrence House maze. It looks very clear from a bird's eye view. It's not a huge maze, more of a walled garden maze. But a great little detailed addition to the game. (The more I play and find things that aren't the main story, the more I NEED to explore and find out what it means.)
Not sure if this is a Shining reference (if so I didn't get it) a mannequin and a dead woman (Wendy and Hallorann from the book, although they didn't die?) And a safe? or just Fallout 76 loot?
If you cruise around on the scaffolding and the balcony's you'll find Danny's tricycle with blocks spelling out REDRUM.
The first reference I found to a Danny was at CAMDEN PARK with his names spelled out in blocks. (Inside the room where you trade in tokens.) Assuming this is the Danny in The Shining and not some other Danny reference.
There are lots of these type of reference Easter eggs in Fallout 76, which I find absolutely loads of fun, the teddy bears that tell stories or Alice in Wonderland Mad Hatter Tea Party, etc., Some are very obvious and some require a bit of thinking.
It doesn't really take away from those rushing through the game (although they're missing some fun!), but does give the explorer/puzzle solver types something else to find and share.
Great job Bethesda on another layer to the fun in Fallout 76!