"Balancing Accounts" by James L. Cambias
James L. Cambias, whose story "Balancing Accounts" is the cover story of the February 2008 issue of F&SF, said in an interview that the story is about a small-time independent robotic space tug called Annie who is hired by a mysterious client for a voyage between two of Saturn’s moons. "During the voyage Annie learns the true nature of her cargo and must fight off pursuers determined to capture or destroy what she’s carrying," Cambias said.
"Balancing Accounts" is Cambias’s attempt to update an old space-opera trope: the scruffy, hand-to-mouth space merchant crew. "I tried to make it work without violating physical laws or realistic economics," he said. "That meant it had to be within the Solar System (no faster-than-light drives) and couldn’t involve a human crew."
The protagonist, Annie, is a robot rocket tug who hauls cargo among the moons of Saturn. "She’s autonomous and ‘incentivized’ — her purpose is to generate income for her owners back on Earth and Mars, and can more or less do whatever she chooses in order to do so," Cambias said. "But Annie has learned that there’s more to life than just earning micrograms of Helium-3; she works just as hard to accumulate ‘non-quantifiable assets’ like the goodwill of her fellow robots, a reputation for honest dealing, and what a human might call friendship."