First, all extra credit projects must be cleared with me before you begin work.  I want to make sure the project is properly focused and on-topic, and that you won't be just spinning your wheels on a project for which I can't give you credit.

Having said that, almost anything goes if it concerns religion and is of interest to you.  The only thing I can't accept or grade would be confessions of faith -- this is an academic class that teaches you about religion and does not teach you to be religious.

Here are some possibilities, but they are just suggestions:

A biographical paper on the life of a religious person.  The person could be well-known, less well-known or unknown to the general public.  The less well-known a person is, the more likely you'll get access to the person for an interview.

A paper on an aspect of religious art.  This could be on religious architecture, crafts (like stained glass), music (say, Christian rock music or Tibetan chant) or any of a great range of possibilities.  Such art is laden with symbols, a subject we have discussed much in class.

Read about the importance of dreams in hunter-gatherer religion and culture. Write a short paper on the subject -- then keep a dream journal for 2 weeks.  How do you interpret your dreams?  How might a person from a hunter-gatherer culture interpret the same dreams?

Do another field study of a religion, choosing a religion very unlike the one you chose for your first project.  Compare and contrast them in the second field study, using the full range of the course material in your analysis.

Do a paper on a specific moral issue, exploring the position of a religion or several religions on it. For instance, abortion, cloning, eating meat, sexual behavior, workplace and professional ethics, war, "justified" self-defense...

Do a paper on on-campus Native American religious sites -- interview faculty who know things about the sites, interview Native Americans for whom the sites have a special and scared meaning.  Apply the course material to an analysis of the sites.
 
Do a research paper on the religious uses of food or a specific food item.  Chocolate, for instance, was used religiously and ritually by the Aztecs, the Maya, and many other ancient peoples of Central and South America.  Most good histories of food (yes, they do exist) discuss the many religious, mythic and ritual uses of food.