This Los Angeles Times opinion piece by David Klinghoffer sparked the interest of Massimo Pigliucci over at Rationally Speaking. I recommend reading them both or at least the latter if you're short on time.
It was pointed out to me at a CFI conference last summer that atheists/secularists/etc devoting too much time to religion. A member or two of the Secular Alliance of IU has spoken up that complementary and alternative medicine should become a focus of ours (a potentially controversial move in this town). I agree and would add that CAM is in general part of larger issues in the public understanding of science.
Anecdotes from Australia and the not-too-long ago study that showed people who reject traditional religion are more likely to hold other paranormal beliefs (such as astrology). A fair number of people do not reject religious beliefs because of the philosophical, scientific, or historical arguments that persuaded many of us. They reject traditional religion because it is pompous, self-righteous, and fails to make the mysterious personal. Criticisms that they frequently lob at science as well.
As seen in the Klinghoffer piece, there's a pervasive belief that science either fails to address or cannot address vitally important aspects of the human condition. While we can easily point out where an individual misunderstands the scientific literature on a topic, what is difficult to persuade mystery-seekers of is that no one can address some of these issues. The failures and blind spots of contemporary science are not a license to invent other explanations or a means to justify of "ancient wisdom."
The critical thinking tools that we use as non-theist naturalists champion are applicable to both religion and paranormal beliefs that haven't been as codified. I am not suggesting that we abandon critiques of religion. I believe religion does need to be opened up to critique, particularly where it interferes in politics, education, and scientific progress. But given the current numbers, we are far more likely to find allies among theists who belief in ghosts than among atheist ghost-hunters.