Skip to bottom for tldr Ok so my first car was a Jeep wrangler and whenever I passed a Jeep wrangler they would wave and I would wave back. I thought that was kinda cool. Come to find out that is a tradition with some vehicles... like wranglers, motorcycles, Corvettes, and Dodge vipers as far as I know. I figure with model 3 being a new cool car there could be a wave for when you pass another 3. I was thinking 2 or 3 finger wave on the steering wheel. Tl;dr get a model 3, 2 finger and thumb or 3 finger wave at other model 3 drivers. Just a thought..