D20-based / Sci-fi-ish Settings...

[Stargrove]

I remember a couple of other companies that did something like this with D20 Traveller and another with D20 Stargate that were both based on 3/3.5 rulesets. D20 Traveller had a few expansions, supplements, and adventures and then died off. D20 Stargate never really went anywhere but for a few supplements. Both settings had huge story potential. But sci-fi RPGs never seem to have much life in them save a few; RIFTS, Spacemaster, older flavors of Traveller, "add your own below". While many of them have been around a long time, they never seemed to have the popularity of fanasty settings. There just seems to be more of a market for fantasy. Feel free to speculate below...

James

[Atrum Ensis]

I would like to point you towards 'Dragonstar' - an out-of-print Science Fantasy setting for D&D 3rd by Fantasy Flight Games. It's still got information floating around the web, after all - you can use the Wayback Machine to find the official website.

[Matthew Shelton]

This is where Starfinder should shine: as a seamless fusion of sci-fi and fantasy tropes. There are a few things Starfinder is locked into, being a d20 RPG: among these are a class system, level-based advancement, and the six attributes.

Class-based games tend to pigeonhole characters into specific roles or social castes. RPGs set in modern or futuristic settings like to have characters be cross-trained and versatile, where specialization is more of an accessory than a critical feature of character design. Fantasy goes entirely the other way, mimicking historical trends of inflexible social strata. By mixing both genres, Starfinder can acknowledge and make use pf the best of both worlds, indeed as the standard game does with the use of class-modifying archetypes, hybrids, gestalts, and regular multiclassing.

The level-based progression simplifies advancement by boosting most everything at once. It's a holdover from the ancestors of Pathfinder, but goes against the grain of sci-fi RPGs which on average let you line-item boost individual class features as preferred. The less versatile advancement can be ameliorated by allowing some retraining rules, and possibly some kind of technological artifacts which can download or modify character personality and experience (like the Matrix) providing instantaneous relearning or forgetting abilities, or perhaps through genetic manipulation rejiggering ability scores on a limited basis.

The fantasy side of Starfinder will let us keep the familiarity of everything we have been playing with, which we can trust as balanced and effective storytelling vehicles. While the tech side lets us explore the vast range of possibilities that go beyond primitive alchemy.

[Bluenose]

I don't think there's much evidence that SF RPGs 'die off' any more than games in other genres. There's a lof of 'dead' fantasy RPGs from the 1970s and 1980s. Sometimes it happens because the licence has ended, sometimes because they hardly sell as well as hoped or a variety of other reasons. Given the small scale of the industry in general it's very easy for a small company producing a product simply to stop doing so for no reason more than the owner lost interest. And really, the comparison with fantasy settings probably isn't one I'd use - a comparison with fantasy settings that aren't D&D or close derivatives doesn't look as unfavourable. I don't think there's any which can match Traveller's Third Imperium for volume of setting content (quality, most notably with some third party material, is another question, though equally some of that was outstanding), and that's a SF setting.

[KarlBob]

Speaking of Spacemaster, Iron Crown Enterprises published an interesting sci-fi/fantasy crossover setting called Dark Space, for use with both Rolemaster and Spacemaster. It was written by Monte Cook.

After a Westworld-style incident where androids killed humans, a backlash against AI (fueled by a splinter sect of the largest religion in the setting) resulted in the replacement of "conventional" high technology (known as hardtech) with advanced bioengineering (called softech). Meanwhile, the barriers holding a variety of Lovecraft-inspired ancient horrors trapped in a nearby nebula are weakening.

There's only one Dark Space book, but it contains plenty of plot hooks and adventure suggestions. The Dell Harris cover and interior art really helps to establish the look and feel of the setting.