When you are with less-experienced players, one thing you can do that has consistently hilarious results is to hit a ball very high. You need a bit of skill to do this, because until you practice it quite a bit, the ball will tend to go out of bounds way past the baseline. Or, you’ll have it drop so close to the net that the opponents can let it bounce, then slam it back at you.
When you get it right, you’ll find that people have considerable trouble returning it well, if at all. They just can’t make the conversion in their minds about waiting (waiting) for the very vertical bounce, and hitting it horizontally back to you. They’ll often miss the ball entirely, and at other times will hit it remarkably out of bounds.
A good server can also serve very high. Sometimes you’ll see that the very best players, who know there’s no serve the opposition can’t return, will a serve very high. There is a limit to the height at which the height of serve is useful, but the good players will often serve it much higher, just for the fun of seeing how high they can serve.
You don’t generally want to try this outdoors on a windy day unless you are pretty sure you can have it land in the right place. But then, if you do, the problems are compounded for the recipients.
You don’t want to do this indoors unless you are good at getting it as high as possible without hitting the ceiling.
You don’t want to do this on a sunny day, with the sun behind you, because that just wouldn’t be fair, or nice, to the recipients.
And finally, you don’t want to do this with absolute beginners, because unless they are warned, they’ll quite possibly run backward to respond and fall, resulting in an injury.