Danny Phantom Easter Egg - "The Hartman Explorer"

Start Watching the episode. You'll know you're almost there when you get to the part where Danny goes into his room and meets Dani. They start talking, and then Dani notices that Danny has pictures of spaceships on his wall. She walks over to look at them, and then the camera zooms in on some of the pictures. The last one shown before the camera angle changes is called the "Hartman Explorer". Hartman is the creator of the show's last name.