A cover letter is the perfect opportunity to explain your talents, hard and soft skills in action. To really stand out from the rest of the candidates, share a story about you that relates to the role you're applying for. Give direct and clear examples of your greatest accomplishments.
At this point, you need to show the person reading who you really are. And because humor is an amazing way to captivate your audience, you could even share a funny story. Just make sure that the story includes your talents and skills.