I don't subscribe to any religion and am pretty anti-religion in general, but I do quite like a few of Anton LaVey's ideas and philosophies, just without the edginess that goes with the majority of his thoughts/followers.
Do unto others as they do unto you...is a pretty good summary and a good subtle counterpoint to the Christian version of do unto others as you would have them do unto you.
As a philosophy, it's much less passive and doesn't prevent you from fucking over someone who fucks with you.
I also like his ideas about life being about seeking pleasure and knowledge and the need to take responsibility for our own actions.
I know that all these ideas are just other philosophers' ideas rehashed, but 15 year old me didn't care about that because it was edgy and 41 year old me doesn't care because that shit actually makes sense and feels comfortable as a way to live my life.