Wow, where do I start?
For myself, I've always been fascinated by religion. I see it as a contagion in the human race, and I'd love to see an end to it. Theists arrive with so much myth, conceit, lies and propaganda that they are not even aware of. I like to point it out when they are simply wrong.
Example; So many arguments in support of theism begin with "Everything has a cause..." or "Order can't come from chaos"....and proceed with 10 paragraphs that stem from these. Neither is true.
Then there are topics such as "Evolution, How?" that should be answered honestly by people who know "how". There is a lot of misinformation that needs to be debunked.
I hold the scientific method in great esteem, and I loathe seeing it attacked in every situation that religions see as a threat, and enthusiastically embraced whenever it does not.
The issue of Intelligent Design is a perfect example of potentially great harm being inflicted upon children....one state in the USA tried to re-define the meaning of "science" !!!!
Next, it is important for theists to understand the POV of atheists. Many can't imagine what could possibly be wrong with having the 10 commandments on a courtroom wall.
So many reasons to debate on this forum, so little time!
Sometimes, we atheists even score a few converts along the way!
and then, there's my tagline.