Whirlwind for me. I was at a boy scout day trip at some lake in NJ. It was a HOT day, and the "seaweed" at the bottom of the lake skeeved me out. I wasn't having it. I turned my introverted attention to the shipping-container-turned-arcade by the rec area. Inside was a Whirlwind, gumball machine, pacman, and maybe a foosball table. Anyway, I saw whirlwind and it's fan topper and thought it would be the best way to cool myself down.
I was hooked pretty much immediately, and it wasn't because the fan offered me sweet heat relief. I thought the game had just the coolest soundtrack, and all I wanted to know was "what would happen if I hit the left ramp when the big red arrow was flashing." I wasn't really a good enough player then to actually make that shot during multiball, so I didn't find out until much later in life.
Still, that allure, music, and sweet fan is what got me hooked from there on out.