PlasmaPig is a fantastic one-button game in which you control a space pig who must protect the motherships from attack. This involves soaring around orbits, picking up speeds and ramming into the enemy.
The pig automatically moves around the orbit of each mothership, and pressing the space bar will cause it to jump from one orbit to the next. Each time you jump, the pig will pick up speed, which is essentially for taking down the larger enemies. Hence, flipping between orbits regularly is the key. Moving around a mothership will also gradually fix it over time.
Later on, ships with shields on one side are added, so you need to move around the orbits and strategically attack from the right direction. It’s really good fun, especially when it gets hectic and multiple motherships are being attacked at the same time.
Definitely give this one a download – you can grab it from The Great Games Experiment.