Commonalities Between Religions

I was thinking yesterday about the requirements for something to be a religion.  I don't know if they are requirements but it seems that all religions have certain commonalities.  For instance they have an explanation for how we all got here, a moral code, and an explanation of what will happen after we die.  Past, present, future. They have sacred scriptures in literate societies which are the codified versions of the stories and laws which were originally oral.  There is (almost?) always a single person who is held up as the best of the ancestors. 

So far, I would say that atheism fits this description fairly well.   I'd imagine that most atheists would dispute that the Origin of the Species is a sacred text, but that's because they can't call anything sacred.  If anything were sacred, that would be. 

My question is about ceremonies.  In part of our need for worship and continuity with the past, we have a built in need for ceremonies.  Does atheism have ceremonies?  What other commonalities are there?