*Pepto Bismol is my friend. Truly.
*Taking migraine meds at a high altitude will make you feel stoned. Even when you don't want to be.
*Americans really are arrogant and entitled. Pointing out the window at the "funny" signs/stores/etc. is a mild example. Asking the taxi driver if his kids go to school is a more serious one.
*Taking toilets seriously is a good idea. Dry (composting) toilets are an excellent invention. Keeping paper out of the sewers isn't a bad idea, either, though I'm not sure it doesn't pose more public health problems. At any rate, I think we're adopting a "if it's yellow, let it mellow" policy in the Plain(s)feminist home.
*My mind is still blown by the existence of homes in which you have to walk outside to get to the kitchen or bathroom (not privvy, but actual bathroom. With running water.) and restaurants which, when you walk around to the back, do not have a back wall. And none of these are overrun with bugs, either. (I know this is common in the U.S. Southwest, as well, but it was new to me, and pretty darn cool!)
*Until now, I haven't properly appreciated Emiliano Zapata.
*There is a radical contingent in Catholicism that might just save the whole thing. (Their existence made me feel better about the annoying, arrogant "Christian" missionaries who flooded the airport.)
*I haven't lost my aptitude for / enjoyment of languages. I really liked trying to learn and pronounce the phrases I needed to get around. (Even if I *had* figured out how to order my dinner, and Halfie offered to order it for me, and I let her. Hmph.)
*The airport bus to Mexico City is a luxury bus, with drinks, even. And video screens for movies.
*It is possible to shower with a cockroach and not mind it.
*Sweetbreads for breakfast - and not the American kind, but actually sweet. breads. - are a wonderful thing, rivaled only by coffee and croissants in Montreal.
*Club music is waaaayyyy better in Cuernavaca than in most U.S. clubs I've been to.
*Taking pictures of people's front doors/laundry/poverty is rude. So is taking pictures of anyone, even your friend, without first asking permission.
*...once you've been there, you have to go back.