I needed this idea the other day, but I can't remember what for. :P How to Build an Easy Glass Bottle Cutter made up of Common Parts DIY Project - The Homestead Survival - Homesteading Re Purposing Tool
Bottle Cutting: there are countless ways to cut or to break a glass bottle or jar, Eternal Tools share our favourite method. This method is fool proof; quick easy, leaves the cleanest cut. 4 easy steps, show you how.