When the Moon Hits Your Eye by John Scalzi

 I found this a fascinating, thought-provoking premise: What if one day, the moon suddenly was made of cheese? No one knows why it happened, but it has a profound effect on the people living on earth. Scalzi tells their stories in a series of sometimes interconnected vignettes involving everyone from diner-goers to astronauts to an obnoxious tycoon. You always expect the good old moon to be up there in the sky, but what happens when you can't count on that anymore? Highly recommended.