Off the top of my head..
-
GTA5
-
Skyrim
-
Fallout: New Vegas
-
The Last of Us: Part 1
-
Half Life 2
-
Portal 2
IMO they are basically flawless and I wouldn't change a thing. Superb experience from start to finish and were literally game changing for the industry.
That last point maybe not so much compared to Fallout 3 as it came first but over all I feel New Vegas was the better, more refined and polished release. Love them both but gotta say I prefer the later