I was finally prompted review this episode after it recently aired on TV Land, but it's long been a favorite (and of my older brother's too).
After spending an evening with Andy and company and watching a TV travelogue about the Carribean, Howard dreams for the island life. After giving it some thought, he quits his job, packs his bags, says good-bye to his friends, and moves there. Once there, he finds it isn't all it's cracked up to be. The island's residents aren't terribly friendly, and there's nothing to do except except soak up the sun. In a dream sequence he loses his mind from boredom, and Andy and Aunt Bea visit and are shocked to see him in this state. Aunt Bea asks how he could give up a good job and decent life for this, and then he wakes up, realizing he made a mistake. Next thing you know, he's back in Mayberry. Andy says, "What about following the rainbow?", and Howard says his pot of gold is right there in Mayberry.
The part about this episode that attracts me is that Howard at least pursued a dream. It wasn't quite what he expected, but he ventured, and only then realized how lucky he was, not altogether unlike George Bailey in the classic movie "It's A Wonderful Life". Not all of us can feel that way about our own lives or our own jobs, mind you, but seeing this episode might plant a seed of courage in those of us who yearn to break out of our ruts and at least pursue the life for us, whatever it may be.