Christopher Nolan's Memento is arguably his best work, and it's subtle touches like this one that got everyone saying things like OMG THIS GUY IS FREAKIN' AMAZING, before Batman Begins was even a thing. Memento tells the story of a guy with memory problems (I forgot the plot), but this moment where - whilst telling an anecdote - Guy Pearce's character, Leonard Shelby, briefly takes the place of a guy in his story, was made for the pause button. Stop it at the right second, then, and you were treated to a sly frame of our protagonist.