If you're here to convince others that you are right and they are wrong, you're wasting your time. It's highly unlikely that it will happen.
At a certain point you realize that you are not going to convince the most ardent believers. However, you can convince those who are unsure of their position and may not vocally participate (i.e. lurkers) in forums, debates, etc. By confronting fundamentalists on such issues as the creation v. evolution "debate" one can make obvious the disparity in evidence between the two positions. Those who are reasonable in their judgement will easily see that the fundamentalists are not driven by evidence, but by faith. Ultimately, that is the good that comes out of sites like these.
To put it bluntly, humanity wins when willful ignorance is fought with evidence.