dear LJ brain trust (glasses)

I'm looking for an eyeglasses solution for bright sunny days. Currently I use clip-on sunglasses when driving and squint the rest of the time, but there's got to be a better way. Here are some parameters:

I don't carry a purse, briefcase, backpack, etc with me all the time, so carrying around an extra pair of glasses is challenging. That said, I'm willing to accept breakage in cheap plastic sunglasses stuffed into a back pocket (or on a belt, or something like that) as a recurring cost. (But not for prescription glasses; that's way too expensive.)

Clip-ons are kind of uncomfortable for routine use.

I'm interested in knowing about tint/polarization/??? options for a sole pair of glasses, if there are any that also work well indoors and at night. 20 or 30 years ago there was a fad called, I think, "photo-gray" -- lenses that automatically darkened or lightened based on light levels. Whatever happened to that approach? (My ideal, I-think-ficticious, pair of glasses involves a little knob for that. :-) )

What other options are there?

religion and profession

osewalrus posted an excellent essay on conflicts between religion and one's profession. He and I agree: you are completely free to practice your religion, but if doing so causes complications in your life, you -- not the rest of society -- need to deal with that.