Any time my youngest cat sees a dog or a strange person near our windows, she'll run up and press herself against the window. She'll make faces at them til they leave. Not sure if she's brave, or just weird.
We were living on the first floor of an apartment, and we often left the back door open. And our neighbors had a boxer who really didn't understand boundaries, so once it came into our house and our cat came out of nowhere, leaped over the couch and smacked it across the face. Me and my dad cracked up laughing.
Reminds me of my old sassy tortoise shell, Skits. We had a German Shepherd who loved to chase her around, he thought of her as a toy. However, given his intimidating appearance and her general dislike for any other pets (how dare they steal her limelight!), it often resulted in her smacking him across the nose on multiple occassions and him yelping/ running away.