I'm now 56 and all my life both parents and my maternal grandmother always claimed, quite off handedly, to be atheists. Mum and Dad were not highly educated but Dad did have a keen lay interest in science and a healthy disrespect for religion, but I always assumed they were simply fobbing off my childs questions as to god, existence etc. Plus, I was made to go to sunday school in my early years, although I had the luxury of chosing whichever denomination I liked at the time (usually presbyterian as they gave out chocolate bars for each given passage of the bible remembered by heart.) This of course only led to a great deal of confusion in my later life but deep down I privately resisted any notion of a god or gods.
In the 1980s I watched with awe Carl Sagan's documentary "Cosmos". In the final segment he commented that at night, when he gazed into the stellar sky he thought to himself "that star and I are made of the same stuff". This simple truth was such a revelation and stayed with me ever since. Now, The God Delusion (I'm on my third reading) has extinguished any lingering doubts and I am grateful to both Richard and Carl for bringing me such clarity and honesty.