This is how I learned about the divine mercy chaplet. I was watching EWTN years ago as I was reverting in my faith and this song and video came on. I watched it and just cried at it's beauty and reverence. Now, at this time I had no knowledge of what this chaplet was, but I felt a need to turn on the TV whenever it came on.
It wasn't until about a year later that I discovered what exactly this was about. Because this song/prayer is sticks so well inside (becomes what we sometimes call an "ear-worm") I learned it by singing it.
Now, I only recite it, and sometimes the song comes into my head at different times... but this is an almost daily chaplet for me :)
PS: The video and this version of the song still brings tears to my eyes :)