LH, the "no rules" comment was mostly a TIC dig at religious doctrine/dogma as "rules." Atheism does indeed have rules (again, IMO) but they're the rules by which the natural world operates, as we understand them based on empirical observation. There may be a variety of philosophies and practices that call themselves "atheisms" but if you get beyond "the evidence does not support the existence of a deity" then you're off into customization country. The answer to the basic question of "does spirituality depend on belief in a deity" is pretty plainly "nope" as far as I can see. Why should it?