Escape Velocity 2
The free demo is available on both PC and Mac. In it, players control a spaceship from a third-person perspective and must defend their mothership from attack by enemy forces. The features rapid-fire lasers that can be used to target enemies, though ammo supplies are limited, making refills through power ups located on the map essential.
Players earn points by defeating enemies that appear from a warp gate. Once they have been destroyed, their worldwide ranking displays on-screen.