How will you get your junk mail in 2929?

In the distant future intergalactic mail delivery is done a little differently: the mail is packed into spheres and blasted into space by giant cannons! Networks of gravity generators adjust the path of the mail spheres and guide them to their destinations. In your role as gravity technician, your job is to plan routes between the mail cannons and space stations, navigating your way around asteroid fields, black holes, space pirates, and other hazards of deep space.

The game has 56 levels with a variety of challenges. The solution for any level can be saved and restored.