Middlefinger?
What about both middle and ring finger up with thumb over index and pinky finger? The two fingers up represent the two bars and the thumb, pinky and index fingers form the B. Sort of like flipping someone off with both the middle and ring finger.
Hmmmm I like this thinking. We def. need someone to show us how that would look. I think I know what your getting at!
Pardon the crude drawing, but something like this
