The Scifi channel?
Ohh...interesting...that might be a good way to get new fans, if you could get it on during Stargate Atlantis or something and make it catchy.
I think you should simply blast the sins logo into the surface of the moon.
Failing that, once you have a demo, get some space on the gaming sites. People who arent decided yet might be swayed by a demo, and you don't want to waste your advertising budget when you havent got the demo ready for them to try immediately when they come to your site. Also, once te 1.03 patch is out and mods are being made, people will be much happier since they can start fiddling with bits of the game they want changed and the forums will be a happier place.
The moon wouldn't work, they'd inevitable miss a letter or something any end up spelling 'Sis' or something

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I personally think a demo up on Fileplanet, Filefront, and the other sites like that would be a lot better than 100 advertisements anywhere (well, except Penny Arcade, which was a great catch for you guys

)