One of my favourites.

As a warning, it's slightly rough around the edges due to the time frame of development, Gamebryo being Gamebryo, and Obsidian being Obsidian. Game can crash but it's far more stable than at release.

One mod I can recommend is Outside Bets (http://www.nexusmods.com/newvegas/mods/46648). Re-adds a lot of NPCs that were cut due to the lack of memory on the 360 and PS3. Each new DLC had to have more from the base game cut. Unfortunately, a different, uncut release wasn't available for PC, but this mod attempts to fix that.

Another is from the lead designer, Joshua "Ropekid" Sawyer, who had some problems with balance concerns even after development/patching was finished. You can find it by searching "je sawyer mod" or checking here: http://fallout.gamepedia.com/JSawyer.

Please check out Pillars of Eternity (http://store.steampowered.com/app/291650/) for an upcoming Obsidian RPG.

Welcome to New Vegas.

(Game's in my inventory. It's the stock/base version. No DLC, sorry. Sale's coming soon though.)