Pinocchio appeared in a Sesame Street News Flash sketch where his nose grew longer every time he told too many lies. His lies would mostly be crazy made-up stories, such as saying his name is Abraham Lincoln, that he can beat Superman, that he became the president of the United States, that he put the sun in his pocket, etc. When he would say the truth (mostly being that his name is Pinocchio), his nose would grow shorter.
Behind the Scenes
The effect of Pinocchio's nose growing longer was done by sticking the puppet to the wall, putting a hole through the center of the puppet's head, and pushing a lavender-colored broom handle through the hole.