Execution of a message is what makes the idea memorable.
WATER. I had this sent to me from a friend, Lalith Dassenaike, who works at Cigar, an organization that deals in water management and sustainable development, among other things. It's a long commercial for Evian, that takes a different look at the lifecycle of a drop of water.
CHILDCARE. This execution about a different kind of childcare, demonstrates an interesting use of outdoor messaging by Grey Worldwide, Mumbai.
If you have any fine examples of how great execution makes a simple idea stand out, please send it my way.
WATER. , again. For World Water Day, 2006, Green Belgium placed these stickers inside wash basins of cinemas, restaurants, pubs etc in Belgium and Mexico City. The stickers photographs of a child's face, placed in such a way that his mouth is exactly positioned where the water goes down the sink. You get the idea... See story here.