If you love sci-fi, and for some reason you haven't heard of this guy, do yourself a favor and read a couple of his books.
We see the Culture dealing with much weaker civilizations in many stories, notably Use of Weapons. Consider Phlebas, Player of Games, and others are about the Culture dealing with significantly weaker civilizations. Excession is about a far superior civilization.
Anyway, I'm still very sad he's gone.
I enjoyed all of the series, but these three really made me realize how amazing the author and the concept of his universe really was. Consider Phlebas is told from the point of view of someone who despises the Culture, which, as an introduction to the series, provides a really unique viewpoint both within the book, and is also generally an interesting literary tool.
A Player of Games is my absolute favorite. I've given copies of this to several friends. It addresses the human problem of what does one do with themselves in a post scarcity existence, especially when advanced AI can just run and do everything.
Outside of the Culture series, I also highly recommend the Algebraist and Feersum Endjinn (sp?).
edit: I forgot to include "Against a Dark Background" in the outside Culture series recommendations. I've read that one a few times, it's quite good. At one point there was talk about making it into a movie, but I haven't heard anything about that in awhile.
The fairly recent Surface Detail was also pretty good, although somewhat horrific in that it deals with the idea of virtual reality hells.
I'm now reading "Player of Games" and it's far better, though maybe the introduction to the "Culture" universe was worth reading the first book.
It seems "Use of Weapons" is the best one, I haven't read it yet.
http://en.wikipedia.org/wiki/List_of_spacecraft_in_the_Cultu...
"No One Knows What The Dead Think", Fast Picket, Culture
GCU Earthlings Can Take Our Names But They Can Never Take Our Gravitas
Player of Games will be one of my all time favorite books for a long time. I can't wait enough to forget all of it so that I can go back and read it once more. I love you Flere-Imsaho!