(I'm going to be doing a series of "elevator pitches" for the White Star Pocket Settings series of posts. Let me know what you think of them.)
Sailing Upon the Sea of Black
In a planetary system of eleven inhabited planets (and an assortment of moons) ships sail the Sea of Black using solar winds. Pirates and privateers, emperors and bandit kings, magic and technology - all vie for supremacy amongst the scattered ruins of the Imperium.
Search for artifacts from the Age of the Imperium, make your fame and fortune under the color of your letter of marquis and perhaps claim a moon of your very own.
Uses both the White Star rules and the Swords & Wizardry White Box rules