While still a student, I met a group of cool young people who were members of the local youth movement KAJ (aka JOC, or "Young Christian Workers"). And because it clicked so well, I also became a member after a while.
The years that followed were among the best of my life, we had a great time together.
The KAJ was founded by Joseph Cardijn, a very special Catholic Cardinal who constantly stood up for the Christian working-class youth and taught them that they too could conquer the world, if they believed in it themselves!