Another vote for The Shockwave Rider, by Brunner - Read that in the late 70s when most of its themes were just a distant dream. In fact a great deal of what Brunner wrote is incredibly forward thinking. Someone already mentioned the wonderful Stand on Zanzibar. Another personal favourite of mine is The Stone That Never Came Down, which foreshadows some ideas more recently explored in the film Limitless. There is also the Sheep Look Up, which deals with the impact of pollution on the planet, some time before most people were too worried about it. Of course I don't know that Brunner is exactly cyberpunk, but much of what he wrote is about how new technology has the potential to influence social structures and culture in positive and negative ways