Basically I believe we should try focusing on areas that can be done individually, but which benefit everyone. We already have forums to work with for most/all parts of CurvedSpace, so we just have to fill them up with.. stuff.

You can try using comparison: would you rather join a clan that already has a set way of things, or a clan that already has a base and will allow you to help build it?
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To start it off, we would need to actually get the message out to recruit people. To do this I think we could simply gather popular sites relating to each of factions, and also sites that specialize in other areas, like GFX, Tech, and general gaming sites. You don't even have to advertise there yourself, we'd just need to gather places that we could advertise in, then release our message in them, and monitor it.
It cannot stop there, though, because friendly accommodation is big part of the recruitment. And I'm not talking about getting them to post an intro thread, or replying to their intro thread. Try to contact people you recruit, or who show interest in the ad, personally, even if it's just a forum PM. It makes them feel more significant and wanted, and that's exactly what they are to us.

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Thoughts? Ideas? Sites? (I will gather some later, I only have time to post this just now)