PC graphics have come a long way since the year 2000, when Deus Ex was our Game of the Year, people were emerging from panic about the breakdown of Western society, and the Lord of the Rings was still but a wonderful book. The YouTube channel Perfect Hand Videos has released a compilation of over half a hundred tech demos from the decade-plus period, showcasing the progression of particle effects, shaders, and shadows. It's sort of like that chart of evolution from apes to humans, but with polygons.
Be forewarned that you'll need about two hours to kill to see the whole thing, and that the video omits AMD/ATI benchmarks. It begins with Nvidia's Grove, and works all the way up to the likes of Arkham City and Hitman: Absolution.