The Simpsons have got to be one of the most beloved families in television history. The award-winning animated series, currently in its 24th season (and not going anywhere soon), is the longest-running sitcom in US television history. Because of this, appearing on the show has become a huge pop culture badge of honor. And if you can feature in an episode as yourself, you know you’ve made it…

Let’s take a look at 20 of the most memorable occasions when celebrities played themselves on The Simpsons.