I know there's some interest out there. For example, there's a web site devoted to an alternative-history book series set in 1623-4 (so far). People submit story ideas, etc., and someone there could probably point out some promising sites.
I know there's fanfic sites out there devoted to all sorts of things (like valuable lessons on how not to write...
They may have ideas.
I belong to a site called Renderosity, which does 3d art, but does have a writer's forum. That's another place
to start. Brass Goggles ( a steampunk forum) has a 'Textural' forum for writers, to the point of even explaining
things like 'Publish on Demand', etc.
There's probably thousands of places. Maybe Google 'writing science fiction', and see what turns up.
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anahl nathrak, uth vas bethude, doth yel dyenvey...