Good call on the peephole card. That would probably work well for short term use. I like to keep spare glasses around, though. I'm reminded of the story of Teddy Roosevelt and his practice of having several pairs of glasses with him. Legend has it that at San Juan Hill he had a half dozen pair! It has been written that when he went to war he stitched a couple spare pair into the lining of his uniform.

I'm not as blind as that but I'm pretty nearsighted. There's no way I could drive without corrective lenses. I actually have contacts and no less than six pair of current-prescription glasses! My main pair is worn in the evenings after I take out my contacts. I have another pair in the glove box of my truck and a pair in my knife & tool case that I use at work. There's one spare pair residing in my partially pre-packed camping backpack (as close as I have to a BOB) and a few more stashed in my room.

All that redundancy stems from an incident where I was down to just one pair, and a beat up one at that. I dozed off wearing them and woke up with one of the bows broken off. It was a major PITA trying to find a tube of Super Glue without my glasses so I could fix my glasses! I vowed never to make that mistake again, so when I got a new pair I made sure to get my PD on the scrip.