He imagined that satellite broadcasting might help a hundred Indian villages save two cows a year and understood what an impact that might have. Says a commenter at PZ Myers' place, on the occasion of Arthur C. Clarke's death. Two cows a year; now that's genius. I can't presume to say whether this came true; I don't have any data on satellites and Bos indicus. But I do have some numbers on fish.
Brough Turner likes to keep track of this stuff, and here's an actual peer-reviewed study. You can get a presentation version here (pdf). On the coast of Kerala, not all that far from Clarke's home, mobile phone networks deployed in stages down the coast between 1997 and 2000; this graph shows what happened next.
Price is on the Y axis, time on the X. Not just that, but the improvement in allocative efficiency led to an 8% increase in the fishermen's profits and a 4% drop in the price to the customer; at the same time, the quantity of fish going to waste went down from 6% of the catch to near zero.
I was given Of Time and Stars as a very little boy; I am frankly terrified by the number of people posting all over the Web to say how much it inspired them with the sense of wonder and joy of science...what future was it preparing us for?