1. Throwbag, or as we say in Swain County, “that thar throwstring”. It’s also necessary to practice with “that thar throwstring” to become competent. Driveways and frontlawns are good practice areas – areas with lots of trees and/or powerlines are not. We like the NRS bag for it's nice swing weight and ease of stuffing.
2.If you’ve got rope, you should probably have a knife. Hopefully you’ll never have to use it but at the very least you’ll have a pointy weapon to fend off hippies with sticky fingers. A blunt tip knife is recommended, as well as a knife with a serated edge.
The Kershaw Knife is well balanced and spring loaded. We also like the fact that it has a very visible red handle and fits perfectly into the shoulder "pocket" of the astral rescue vests we use.
3. Extra drainplug, because yours will always blow off on the interstate. (Drainplugs are of course boat-manufacturer specific)
4.Ducttape, wrap a little around a stick (or your paddle shaft)and tuck it in your pfd. You will need this to cover your drainplug hole when you lose your spare drainplug. (Ducttape on a stick is also my first-aid kit)
5. Carabiner, to strap in shoes or other gear so it doesn’t wash out when we swim, oops I mean, when our skirts implode and we somehow get sucked out of the boat.
This Kong Anodized biner works well for our needs as it's big enough to hook around a paddle shaft. Of course, you'll want a locking biner for more advanced resuce scenerios, ie. z-drags and rescue swimming