The oldest video game in my collection is a 2 player Computer Space cabinet (glittery green color). One of the neat gameplay elements is that shots are implemented just as a distance in front of your ship that increases over time until it hits something or reaches a maximum distance. The play field also wraps at the screen edges so you can do things like fire off screen and then rotate your ship to curve your shot into the other player. It's unusual enough that most don't expect it.