kitler53 on 18 September 2013
if you strip away all religious holidays, state based patriotic holidays, and non-religous historical or traditional holidays the one that comes to mind as being very atheistic is pi day. Pi (3.14159..) is celebrated in march 14 (3/14) by baking and eating a pie. I feel it celebrates my resonance with the facts and evidence found in math and science over religions resonance with faith and belief.
there is also mole day but there isn't really an obvious way to celebrate it.
