Fairly Oddparents, The Easter Egg - Dash from Danny Phantom.

In the episode Fly Guy where Timmy Turner wishes he was a fly so he could watch "I was a teenage fly", the teenager who is transformed into a fly wears a red sports jacket, blue jeans, has blue eyes and blond hair. These are the exact physical traits as Dash the jock bully from Danny Phantom; he also has the same voice!