The scale of measuring how exceptionally angry someone is getting, particularly where the cause or causes are either unclear or irrational. From famous spokesman of the irrationally foaming at the mouth, Newt Gingrich.
Mr. X: I can't believe it! WTF? THIS IS ABSOLUTE MADNESS! I'M LITERALLY SHAKING WITH ANGER! (Roared with flecks of spit flying from the side of his mouth)
Mr. Y: Jesus, that guy's gotta be pushing an... 8, 9 on the Gingrich scale?
Mrs. Z: Hell, he's going all out. Better run, if he hits a 10, his head's gonna explode and I don't want any on me.