Fiona Snabblejax is a resident of Teras Terrace who makes her living running a black market of goods forbidden by Pretorius Technologies to be brought into the Terrace. She is cagey about her sources, but she has access to technologies Pretorius would rather keep secret, as well as to strange things gathered from many different worlds. And what she doesn't have handy, she can usually acquire, for the right price.
Although Fiona likes playing up her image as a sinister figure of mystery, most (though by no means all) of her black market goods are perfectly innocuous items that are banned for obscure administrative or political reasons. (One of her top-selling wares, for instance, is peanut butter, which for some reason Pretorius Technologies prohibits.) Furthermore, though she doesn't talk about the fact, she actually donates a large share of her profits to various charities.