Personally, I find a lot of the vaults to have really interesting stories, particularly those that Vault-Tec Industries did social experiments on (Project Societal Preservation Program).
Anyone else out there whos the same? And if so, is there one vault (either from NV or any of the other Fallout games) whose storyline really stood out for you?

For me it'd probably be Vault 11 (NV), where the social experiment was telling the inhabitants they must kill one every year, otherwise they all die. Such a great, intriguing story IMO (and the ending is insane!).
I also found Vault 92 (3) an interesting one, where subliminal messages were hidden within white noise to the music genius inhabitants; but I've only read a basic summary of it.