Along your athiest lines, my favourite quote is:
That which can be asserted without evidence can be dismissed without evidence. - Christopher Hitchens.
(although I apply this more to pseudo-science than to religion).
And on science:
The good thing about science is that it's true whether or not you believe in it. - Neil Degrasse Tyson.
But evolution is only a theory!”, which is true, it is a theory, it’s good that they say that, I think, it gives you hope, doesn’t it, that - that maybe they feel the same way about the theory of gravity… and they might just float the f*ck away. Tim Minchin.
And just general loveliness:
Somewhere, something incredible is waiting to be known. Carl Sagan.
Don't be fooled by their innocent looks. All Emmas Are Evil. And they're coming for you.
Hitched Awards 2013 - officially a scary blunt.