Stump the Buff is a segment created by Tim Heidecker for his show On Cinema at the Cinema. It consists of Tim quizzing frequent guest Gregg Turkington on various movie trivia questions.

An early version of Stump the Buff was released as a bonus episode of the On Cinema podcast. It was available for 99¢.^[1]

Stump the Buff was first publicly featured during the 1st Annual On Cinema Oscar Special, consisting of three Oscar-related questions. The prize was a VHS copy of The Lonely Lady. Gregg was marked incorrect for all three questions.

Tim sprung another round of Stump the Buff on Gregg during On Cinema at the Cinema Season 2 Episode 7: "The Croods", with a special prize. Thing X pledged that for every question correctly answered by Gregg, $500 would be donated to the American Cancer Society. Gregg was marked incorrect for all five questions, raising a total of $0.00.

A special themed version of the game was played during On Cinema at the Cinema Season 7 Episode 7: "Jem and the Holograms" and "Paranormal Activity: The Ghost Dimensions", in which the questions and/or answers all had to do with “lucky number seven.” Gregg was once again marked incorrect for all three questions.

A version of the segment was performed at oncinemalive, where audience members would compete for a Carrabba's Italian Grill gift cards.