Peregrin Took
Peregrin Took, better known as Pippin, is one of the four Hobbits who helped Frodo leave the Shire secretly in The Lord of the Rings. He had more curiosity than was good for him, which twice endangered the Fellowship of the Ring. He threw a stone down the well in Moria, which alerted the Orcs and aroused the Balrog. In The Two Towers, he stole from Gandalf the palantir which he had saved from the waters of Saruman's destroyed fortress, and looking into it was interrogated by Sauron.
Gandalf healed him and forgave him, carrying him on horseback to the fortress-city of the last Steward of Gondor, where he entered into the service of the city and was instrumental in preventing the murder of Faramir.
Films
In Peter Jackson's film adaptations of Lord of the Rings, Pippin is played by Billy Boyd.