My one just doesn't seem to be able to judge spaces too well, like she'll run full pelt for the gap between the banisters and just sort of wack it.
Another time she kept backing up, running and throwing herself at our glass back door to get in over and over until the thuds alerted us.. This was when we first got her as a kitten. It took her a while to understand how the door needed to be opened first.
She also has a habit of rolling in ecstasy on the bed and falling off.