For some reason sunsets are one of the things people name when they try to think of things that are beautiful, or make them happy, or even... are good. Perhaps this is because each sunset is different. This evening's - pictured above a few seconds before the sun disappeared into a bank of cloud - was a three-ring circus! (Give it a click, it's full of lovely details.)
Perhaps it's also because sunsets let us consciously participate in the passage of time. And in a world larger than our own, of which ours is a natural part.