Tennis balls have all sorts of creative (and cute) uses around the house, and there's a pretty good chance you have one sitting around somewhere. If you need a quick way to stop a door knob from slamming into the wall, a tennis ball will do the trick.
If you have kids or tend to swing doors open excitedly, door knobs have the potential to wreck your walls. YouTuber kipkay demonstrates on his channel how to cut a tennis ball to fit around a door handle to prevent that.
Once you place it on the door knob, it will provide just enough cushion to absorb the force. Of course, a really forceful swing could still potentially cause some damage, but this should prevent most of the damage. If you have a couple of tennis balls lying around, you can make a useful lid-removing grip too.
5 Clever Uses for Tennis Balls [YouTube]