Not to toot my own horn, but I took a shot at it this year as well: http://www.wallsofthecity.net/2007/10/happy_hal... . Did not come out too bad, all things considered, but the Serenity one up there beats mine all to hell.
Well, now the question simply becomes whether we focus our attention on generation-ships, or on better engines. We have, more or less, the capability to get to this rock right now... but the expenditure of funds would be massive, and the time necessary would require the construction of a ship capable of supporting people for many, many generations (making it even more expensive).
Anywise, I never found science and Christianity to be at odds all that much either, but I have odd views to begin with :).