Heck yeah! I have had heated discussions with people I have disagreed with. The key is, that either in the discussion or through PM’ing, we have ended up respecting each other in spite of our differences.
I am a Christian but there is a huge atheist population here on fluther. I think most of them respect me because I am not afraid to speak my mind, but I respect their right to have different opinions, and I don’t try to proselytize them. I also don’t buy into all the right wing fundamentalist hate mongering and Christians like me are often scared to speak out against other Christians when they hate. I think my willingness to call other Christians out when they do that earns their (the atheists) respect. I also expect my atheist friends to treat me with the same respect I give them and here on fluther they really do.
If you know people here and look at my fluther you might be surprised to see right wing fanatics right next to left wing fanatics. There is some grain of truth in just about every-one’s point of view. If you respect that, and keep an open mind, you can be friends with a huge variety of people, without totally agreeing with them and while maintaining you principals.