Every time someone mentions an interesting book, I make a note of it. Then a couple times a month, I go back through my notes, pop open a website that shall not be named, snag em all, throw them into calibre-web and sync them down to my ereader. I can get hours of enjoyment from a 1-2MB file, and I love that. Same for older cartridge-format game roms, a N64 rom is generally under 50MB and can keep me busy for days, an NES or GB ROM is usually smaller file size than a book, and some great old DOS games clock in at a handful of MB.
What other great bang-for-the-storage-buck stuff is out there that you enjoy?
Weighing in at 4.0MB, I present to you the SNES roguelike Mystery Dungeon 2: Shiren the Wanderer (or Fushigi no Dungeon 2: Fuurai no Shiren).
The original console “RPG you can play 1000 times”. It’s tough but fair. It stops just short of permadeath; dying sends you back to the start at level 1 with nothing, but you keep your side quest progress and any gear you had the foresight to send back to town before you died. Watch someone stream this sometime. It’s turn-based, but the tension is like nothing else I’ve ever played.