Take The Bridges of Madison County. It's a long, simple story, and many of its scenes feature Meryl Streep and Clint Eastwood sitting at Meryl's kitchen table. However, the movie is incredibly compelling not only because of the strong performances, but also because of the shifts of power. In the first half, Meryl holds the power. She hasn't yet decided how she feels about this stranger. She can kick him out whenever she wants to. She can let him get to know just a little a bit about her, or everything. She can have an affair with him, or not.
In the second half, the power shifts to Clint. Meryl's feelings have started to win out over her better judgment. She feels torn and guilty, held back by the ticking clock of her husband and children's return home. Now Clint has the power, since he will be the one to leave her - both physically and emotionally.
Beyond that, each scene can be marked as a "win" or "loss" for Meryl and Clint. When Clint says something too provocative and Meryl closes him out, he loses. When Meryl starts to regret her decisions, she loses. Here is a great scene of one of Clint's losses:
The "win" or "loss" concept is also featured in Stranger Than Fiction (one of my faves!) when Will Ferrell starts marking off moments in his life as comedy or tragedy. Since he's hoping for a comedy in which he can survive, the comedic moments are wins and the tragic moments are losses.