I would have loved the original Fallout so much more had the planned mutant raccoon faction made it into the game. VG Facts' "Leftovers" series looks at the S'lanter faction, extra maps, the planned Supermutant invasion and other bits left out of the post-apocalyptic classic.
Fallout spent three years in development as a game based on Steve Jackson's GURPS table-top role-playing rules, switching over to Interplay's own SPECIAL game system in the final year of development, so this was not a project that shied away from making sweeping changes in order to stick to a coherent vision.
Thus we wind up with secret items that have no purpose in the game, echos of quests and storylines that didn't make the cut. Maps that were never used, and an entire race of Raccoon people that I never got to alternately shoot and cuddle. What a disappointment.