Hm... This is an interesting concept for a thread.
I'm an atheist and I guess the word I'd most associate with it is... 'Nothing'? It's kind of a funny thing for me to try to describe; a lack of belief. It is just that: The absence of any religious/supernatural belief.
For anyone curious, the reason I view myself as an atheist, rather than an agnostic, is because I'm describing whether or not I believe in a deity, not whether or not one might exist. Of course I don't know what will happen after I die, or if there is a god or something else supernatural out there. I just personally don't feel that there is, therefore I call myself an atheist.
As for what one word descriptions I would use for my feelings on other religions? Well, the only one I have any real familiarity with would be Christianity. Hm... I don't know... So many different things come to mind when I think of it that it's hard to put it into one word. I think I'm going to go with 'Angel'. Why? I like the concept of angels, even if I don't believe in them. It's wonderful imagery to play with when writing poetry, or drawing art, etc. I have no idea if angels are in any way exclusive to Christianity, but that's where I learned of them, and what I associate them with. Most likely, countless other religions have angels in their holy texts, too.