I had to trim about 1" from a piece of glass I was installing in a cabinet door. But even after scoring the glass with a cutter, it kept breaking off in small pieces.

I figured if I could snap the whole length at once, I'd get a nice clean break. So I sandwiched the waste piece of glass between two scraps of hardwood as long as the scored line and clamped them in place as shown in the drawing at top. Using the clamp as a handle, I gave a quick downward snap, and the piece broke off perfectly.
—Allan Fanjoy, Saint John, N.B.