I just love the concept of megastructures like this. There is currently an ongoing story in Reddit's r/HFY short story subreddit that has one story thread taki

I just love the concept of megastructures like this. There is currently an ongoing story in Reddit's r/HFY short story subreddit that has one story thread taking place on a Matrioshka Brain built around a singularity in an alternate dimension. The massive brain, among other things, houses the uploaded mental engrams of all Humans, as a final "You can't get to us" line of defense against whatever threat might arise. Interesting concept, I thought.