I'm pretty excellent at censoring myself. The typical conversation around my house would not be appropriate in most places. And I typically don't bring up controversial subjects unless
1) I think it will be a good discussion
2) I want to piss someone off, which usually involves...
3) I'm drunk
Somewhat off topic:
My best friend swears in public all the time and will discuss things like
Alabama hot pockets (Urban Dictionary link- NSFW text) in a restaurant with little kids sitting in the booth next to us. I don't get how he can't at least tone it down in public.
Once I started to let a "that's what she said" slip while bowling with a VP at a company event. Yes, I have a childish sense of humor.