These are the best ultralight tools I have found. They all fit on a keychain:
ThruNite Ti3 Flashlight — produces 120 lumens — waterproofed to IPX-8 — impact resistant — use a single AAA battery
Titan Plus Flashlight — produces 300 lumens of light — durable construction — waterproof — made in USA
RovyVon A3 Flashlight — produces 700 lumens — IPX-65 water-resistant — waterproofed to IPX-65
Nite Ize Inka Pen — writes underwater — writes in temperature from -30 degrees to +300 degrees — ultralight — made in USA
Leatherman Micra — ultralight mult-itool — includes scissors — made in USA
World’s Smallest Titanium Toothpick — a portable toothpick made out of titanium
Quick Release Keychain Clip — ultralight titanium clip for a keychain
