Looking thru this thread and a few others, there are a few things I thought of that I havn't seen on to many's list;
Duct Tape, the universal tool
Zip ties. almost as usefull as duct tape
Bungees, for fastening items to large for zip ties.
Ziplock bags. for keeping tinder and matches dry, and in a pinch as a canteen.
I am also including nails and screws in my Bug out kit. If I need to make a shelter it's faster than paracord lashing.
Aluminium foil great for storing excess food after cooking, good to make a wind break for a camp stove, caa be used in place of a pot in a pinch.