I've been thinking about Mexico City a lot while working on a related writing project and I just remembered my final moments in the city. They speak volumes about el D.F.
I had a pleasant conversation with the taxi driver as he sped through the city center toward the airport. He repeatedly complimented me on my speaking skills and my neutral accent as I described the purpose of my nine-week trip and expressed slight worry over the work it would take to maintain what I'd gained once back in San Francisco. He was a nice guy who inflated my ego a bit.
Then we arrived at the airport and, despite someone at the guesthouse telling me how much the ride would cost, I asked him how much I owed him, you know, because that's what people do. Sure enough, he gave me an inflated figure. It turned out to be exactly what I had left in pesos. I wasn't too bothered. It was what I had planned to give him, only now he wouldn't be receiving a tip.
I was the one who got the tip: never trust cab drivers, especially the friendly ones (and especially the defeños). Cabrón.