I'm sure I'm not the only person who has set down a small allen wrench along side the road and been unable to find it, especially on dark and rainy days.
All the tools in my portable tool kit, and many of my shop tools, now sport garish finishes -- bright yellow rubber on the grips of larger tools, and neon orange paint on smaller ones. Very handy when doing repairs after dark, plus the rubber dip stops most of those annoying tool bag clinks and rattles.
Also, if you have a spoke wrench with multiple sizes, a dab of paint next to the one that fits your spokes will speed truing and help avoid stripping spokes by using too loose a size when you're in a hurry.
Rubber coating for tool handles is available in most good hardware stores. Plasti-Dip is the most common brand. It is available as either a dip or a spray. The dip makes a better coating in my experience.
Almost any spray paint will do for making tools visible, but the best in my experience are obnoxious OSHA safety colors for hard hats. They're colors that don't appear in nature, that's for sure.
This page written by Josh Putnam. Please feel free to email questions, comments, corrections, suggestions, etc.