I've been "out" as an unbeliever all of my life. I remember discussions with friends in high school about religion and the feeling of utter disbelief that adults actually believe this stuff. One of my best friends in High School's parents were both unitarian ministers in town.
I haven't really cared much about atheism until I started reading about the horrors of the Catholic Church rapes in Springfield, MA (near where I live) and also in Boston (where I was born). Someone forwarded me a link to http://bishopaccountability.org and that's when I started getting angry. I was 44 at the time. That was 5 years ago. Now I am one of the most out-spoken atheists in my community.
I have had death threats by email, phone calls that were very frightening to my wife and family (we now have an unlisted number). Someone sent us 50 pizzas last year, and I've had my email registered at dozens of gay porn and fetish websites over the years. Thank goodness for Google, their spam filters are excellent. One of those people who submitted my email to a gay porn website unfortunately didn't know that her IP address was also included. I was able to track her down with some assistance from a skip tracer friend of mine, to a little trailer park in the mid west. One phone call put a stop to that nonsense.
I am a music teacher in my area. All of my students know my position on theism. Quite a number of them are religious or come from religious families. It's made for some interesting conversations over the years!