I guess most of us have an established practice routine. Etudes, scales, chords etc. I also guess most of us get tired of it from time to time and want something fresh and different to practice for a while. Something that inspires us to learn something new. Here's a video I found a few weeks ago, that made me want to learn to play it. Not too difficult, but with some challenges. (Speed down the video to see the technique clearly). Feel free to add more examples.