5. Elijah Wood
Elijah Wood appears as "Ethan", a student in "Iced, Iced Babies", the sixth episode of season 2 of American Dad! Ethan is a student at Groff Community College who is inspired by Roger, posing as a professor, who tells him to make positive changes in his life. When Roger and Hayley arrive at Ethan's mansion later, however, they learn the "positive changes" Ethan made included stabbing his father to death. After informing Ethan that he isn't a real professor, the student is horrified that he killed his father because of Roger's bogus advice, and has a nervous breakdown. Wood is best known for his role as Frodo Baggins in the Lord of the Rings trilogy, and has appeared in numerous films since.