A friend of mine overcame his stuttering problem by imagining himself as an actor in a play. That is, he wasn't himself struggling in conversation, but an actor saying his lines deliberately and confidently. He would pause for his line and then deliver it. He says he got the idea from a singer who famously stuttered but sang flawlessly, and the fact that he himself could do things like read aloud and recite poetry with no problems. It's pretty cool, because he always has this thoughtful pause before he speaks and it makes everything he says seem profound. He says it's second nature now.