Marv - Not for screwdrivers but color coding for hex wrenches sure beats having to grab a caliper to find the right size.
I made a little project of figuring out the right size shrink tubing for a minimum number of hex size ranges. It has to fit cold and shrink tight hot. Then determine the number of basic set types (Metric or US, plain hex, ball end, spline drive (rare), good material vs cheap import, and whatever other distinctions are important.
The idea is that you put little pieces on the wrench up by the turn in a sequence like the color coding of resistors. I used a top band of red only for the metric ones. Red is the color code for anything metric in my shop.
Then I went on eBay and after a couple of false starts, that left me with a lifetime supply of shrink tube, hunted down the exact sizes and colors of shrink tubing for my system. Chinese sources are cheap and ship relatively fast.
By the way, this approach can be also used on other tools with small diameter features. Like color code dark blue for the simple tools which must always live in the kitchen where my wife knows to look. BTW, buy her the best quality tools you can afford. Same as when your kids are old enough to take care of their own tools. Ed Weldon

"equal sizes arranged alphabetically by handle color"