Oh Gaff is great when you have it. And yes, it finds its way to mysteriously wander off. To prevent said problem, take a trick of the trade from the electricians. Like they do their Crecent wrench (and everything else) to their body, a piece of tie and a beaner go a long way in keeping your gaff at your side. Found this one out quickly when hanging a show all by ladder. Once that roll is attached and ready to rip, or unattach for uses on a big floor, it's not walking away unless the spitful carp comes by with his leatherman/gerber and cuts it from you while your back is turned. At that point game is on for what you do to him.
Oh and a bit of GooGone works wonders in getting that residue off of stuff (especially cable). And Silver Metalic Sharpies work great to write on black or other dark colored gaff. plus it looks really cool.