Not a big thing, but did anyone else notice, if you hacked Sarah's computer in Vault 21, the e-mail from the guest referring to her influential husband Biff Tann (Biff Tannen)? Thought it was possibly an interesting little Back to the Future egg.
There's another possible Back To The Future reference. If you have INT > 6, you can tell Joe Cobb that if you take over Goodsprings, the people there will be forced to work for him. He says, "Mayor? I like the sound of that!" just like Goldie Wilson.