What you say when somebody gets over-hyper and starts jabbering on and on, or uses their outdoor voice on a subject you personally think is undeserving of the effort or don't really care to hear the whole story about. Say to somebody who starts sweating profusely while talking.
Joe: "Look, I told you not to play my ps3. You always scratch the discs and never put them back in..."
You: "Calm down, James Brown. Damn. I wasn't anywhere near it."
Jenkins: "I just wanted you to come out for a beer, but no. You had to leave me hanging by myself and I got kicked out of the bar and..."
You: "Calm down, James Brown. I had my own shit to deal with."