Yes. There are a few religions that members can also be atheist.
No. An atheist can not be a member of any religion.
"it is necessary to keep in mind that atheism is nothing more than absence belief in the existence of gods. Atheism is not the absence of religion, the absence of belief in the supernatural, the absence of superstitions, the absence of irrational beliefs, etc. Because of this, there is no inherent barrier preventing atheism from being part of a religious belief system." Source http://atheism.about.com/od/atheismquestions/a/AtheismReligion.htm
Only the pretence of belief is required to be a member. Because, like the god, belief cannot be tested. This encourages people to lie about their beliefs, because religions often oppress anyone who's not in the club and you can profit if you're a leader there.
There are some established religions that have atheistic ideas but incorporate teaching from religious texts. For example, Christian Atheists follow moral teachings of Jesus Christ but do not believe in Genesis, God, and etc.
Buddhism and Daosim are okay.
Sure.... I, at times, consider myself a Unitarian.
Atheism-lack of belief in god Religion-A particular system of faith and worship Atheists can still follow a system of worship, it's just that the subject of worship wouldn't be a god, or gods. The term your looking for is Theism.
if they choose to be, they can.
Satanism is a prime example. There are atheistic denominations in which the atheist believe them self to be their own God. Therefore, with Satanism being a religion, atheists can be in one.
Well no, they are denying an existence of G-d or gods and therefore don't belong to a religion.
How? They deny the belief in an entity. I guess they could be some kind of spiritualist, but isn't there an entity of some sort in any spiritualism?
No. It's denying a religion.
As an atheist myself, I do not want to see temples of atheism or groups of atheists trying to conform other religions. Atheism is simply not being involved in religion or not believing in any religious practices. A religion is a study of a god, to which atheists have none, or at the least do not believe they have one.
Technically, the term for this would be agnostic.
You can believe in God without being religious but atheists can't be religious by choice.
It's like saying not playing football is as much a sport as playing it.