http://buddhism.about.com/od/basicbu...dhaatheism.htmIfatheismis the absence of belief in gods, then many Buddhists are, indeed, atheists.Buddhism is not about either believing or not believing in God or gods. Rather, the historical Buddha taught that believing in gods was not useful for those seeking to realize enlightenment. In other words, God is unnecessary in Buddhism. For this reason, Buddhism is more accurately called nontheistic than atheistic.
http://atheism.about.com/library/glo...f_hinduism.htmMost people regard Hinduism as polytheistic - an idea which is both true and false. It is true that Hinduism has polytheitic elements, but it also as monotheistic and atheistic elements as well. It is diffiicult to describe, but polytheism is simply one way for a person to look at Hinduism. The variety of deities provides people with a variety of ways to fulfill their spiritual needs. Some go further and regard all of the deities as merely aspects of a few, or perhaps of just one deity. Some fo further yet and regard it all as manifestations of a single, impersonal ground of being - not theistic at all. In the end, Hinduism is what one makes of it.
As for Unitarians - they explicitly welcome atheist and agnostic members, accepting and valuing all worldviews is sort of what Unitarianism is about.