Sounds weird, right? Silent film is a great study in body language and acting. You need to be aware of what your body is doing at all times!
Here are a few films you can watch right now:
Charlie Chaplin's Gold Rush: https://www.youtube.com/watch?v=f8v79UCDq6I
Fritz Lang's Metropolis: https://www.youtube.com/watch?v=-I9FD21k7Cs
FW Murnau's Nosferatu: https://www.youtube.com/watch?v=FC6jFoYm3xs