I follow the Hellenic religion. I do not believe in the existence of a God, but I rather follow the rules of religion as a way of life. For instance, I do not consider children born out of wedlock cursed as other religions did and do. Other things are adoration of the human body, adoration of nature, sports playing a key role in everyday life, etc. The principles of the Hellenic religion are almost identical to the post-60s cultural norm.
In my neighborhood, I can think of at least three people who either believe in the Hellenic religion or in a mix of Christian-Hellenic worship.
Fun fact: Greeks that follow Jesus are called Rhomaioi(Romans) because of the Byzantine Empire(Eastern Roman Empire), and Greeks that follow the old religion are called Ethnikoi(Nationals).