Maybe this is already known, but there is a cool Easter Egg in Star Trek: The Next Generation:

When you are given the choice of getting points or doing the "shuttle simulation", instead of hitting the left or right flippers, hold down on the launch button, then press the right flipper to activate the simulation.

Instead of the shuttle simulation you will play a hand of poker with Commander Riker instead!

There are also some with music/ callouts from other tables but this could just be reusing them, still nice to look out for, can't remember when I've spotted them so if anyone else can, possibly one from Arabian Nights being one example?...

Similarly some tables feature easter eggs such as characters from other tables and sometimes games by the same firm in the art and features. Quite fun to look out for these too.

And of course at least one of them plays Pinball Wizard (The Party Zone and obviously The Who's Tommy Pinball Wizard the one based on the film that's not in the game does as it has 21 of those songs in it)

Addams Family and a few others have a dirty pool callout when you land the ball behind the target in question with the dirty pool shot method (a pinball skill trick)

There is also one for star trek the next generation, if you hit left and right bumper while the character "Data" (noticeable by his over detailed explanation of how to do better) after you have lost a ball, you will hear another character (Captain Picard) Saying "Thank you Mr Data", there is also a display along with a point bonus with this.

There's a few for Judge Dredd, all of them using "push red button" prompts (mapped by default to the L and R Ctrl). They do stuff during the following:

When JD says "get the extra ball!"

When the Safecracker looks at the player after jostling the old man-activates "Hungry Hurry Up"

When the Sniper Tower is collected twice: as soon as the perp's impaled on the fence, a dog walks by and pees on the body.

I just said that last one about a pinball game, right?