The Fallout: New Vegas mod community has been admirably strong, continually providing reason after reason to replay an already great game. Heck, even Obsidian's own Josh Sawyer got in on the action with a sweet hardcore mod.
Well, now I've got yet another one for you, or rather, a series of mods with the same purpose: to restore cut content. You've probably seen these kinds of mods before with previous Fallout games or another Obsidian game known as Knights of the Old Republic 2, and this is in a similar vein.
Essentially, content cut from games all the time before shipping, whether at the last minute, early in development, or at any stage really. Thing is, you can sometimes find it still lying around in the game code, which modders then can fiddle around with in their spare time (something developers don't have), and bring it back in with tender loving care.
That's the case with a series of mods from 'Moburma' which you can find here. Right now they're all in chunks -- hopefully at some point they're merged together into a 'Complete Edition' mod or similar. Note some mods may be incompatible with each other, so read the notes for each.
If you feel like reading a novel on this topic, Moburma has extensive notes on his findings and process and also a preview of what the future might hold right this way.