Gas caps. I've never really given them much thought. I don't believe I've ever lost one, or at least not in the past 10 years. My car (a Fiat) has a cap that can only be removed and replaced with the car key so you can't really lose it. Husband's car (a Ford - I know, I know) has a cap that's attached by a squiggly cord so you can't really lose his either. Who knew that we actually needed to progress beyond that?
Because apparently, we do. I have a client who works for a company that is developing a gas tank that doesn't have a cap. He's a very nice guy, the classes are enjoyable, and as a bonus, I'm learning all kinds of useless (for me) technical automotive jargon.
I've also learned that the particular capless system my client has developed is not exploitable in the US. Why, one might ask. Well, the country that pollutes more than any other country on the planet has stricter permeation standards than Europe. Kind of funny, don't you think? So, the permeation thing, from what I gather, is about the allowable amount of toxicity that can permeate the material of the capless system. We talked about the ridiculousness of such a situation and then we laughed, because, really, what else can you do?
Which is not to say that I think it's a bad thing to have strict permeation standards. Au contraire, I think we should all be very strict about toxic permeation levels, in all areas of life.