I've come across a wonderful Snape, who happens to be Catholic, although that is not the focus of his characterization. I find Rebecca Webb's Smallest Slytherin (http://cda.morris.umn.edu/~webbrl/SmallestSlytherin/) trilogy of novel-lenth fics to be delightful, if more than a bit AU. (I actually like her Harry and Draco much more than Rowling's!)
no subject
You might want to give her Catholic!Snape a try.
Persephone