I think I came across this story of the starfish in a book once and I tracked it down again online recently to pass it forward to you. Here it is – enjoy!
As the old man walked down a Spanish beach at dawn, he saw ahead of him what he thought to be a dancer. The young man was running across the sand, rhythmically bending down to pick up a stranded starfish and throw it far into the sea.
The old man gazed in wonder as the young soul again and again threw the small starfish from the sand into the water. The old man approached him and asked why he spent so much energy doing what seemed a waste of time. The young man explained that the stranded starfish would die if left until the morning sun. “But there are thousands of miles of beach, and miles and miles of starfish. How can your effort make any difference?” The young man looked down at the small starfish in his hand, and as he threw it to safety in the sea, said, “It makes a difference to this one!”
Source: http://www.noogenesis.com/pineapple/starfish.html