Going by a few other post, this thread is about powerful lyrics. I wasn't sure if you meant like a powerful drive or lyrics.
Mine is Antarctica by Hands Like Houses. To get pretentious and "deep" here. The song always reminds that before I can succeed, I need to fail and just keep trying. I really hate to sound like one of those tweens who say music saved them, but this song has helped me through some tough times. And it's filled with Peter Pan references, so it just wins everything.