Let’s start a wave. Just for the fun of it.
Just start waving at people. Open your car window and wave as a friend drives by, wave to the runner going by your house when you walk out to get the mail, raise up your hand and say hi to that guy walking towards you on the street. Do something really nuts and just wave to that lady across the street. Wave at all of the people that you know, and try to wave to as many of those that you don't.
Who cares if you know them, they know you, or some people will think you are a nut job. Some of those people will have their day brightened by you waving and saying hi. Some people will think you are a bit batty, but heck - who amongst us is not a bit off? Some folks will respond with a look of "what the heck does that weird person want from me", and hopefully that makes you laugh. Some will have no idea how to respond because they are used to the habit of looking at the ground, sky, their watch or cell phone, or anything other than good old eye contact and a wave.
Just try it - and share any good stories about the kind of reaction you get. Only if it is a positive story though. :)
If anyone does not respond well, just tell them it was a crazy idea you heard about online. And then wave as you say goodbye.
Raise you hand when you see other humans - wave it back and forth. Ride the Wave.