When I speak English, apparently (unbelievably) there is still a hint of a foreign accent somewhere in there. So when I meet new people they usually get curious about it. They can hear I’m foreign, but they can’t ever place me as Mexican, as I don’t look like the average Mexican.
Lately, I have changed my default answers. It’s fun and goes something like this:

Marcos and a new acquaintance are introduced by a third party. A few seconds of smalltalk ensue, followed by the inevitable question.

NA (New acquaintance): So tell me, Marcos. Where are you from?

MK (Marcos): I’m from Chicago.

NA: Oh, O.K. But where are you from originally?

MK: I’m from Chicago.

NA: Really? Where is that accent from then?

MK: Accent? Oh, that’s no accent. I have a speech impediment.

Uncomfortable silence. The look on NA’s face is priceless at this moment. Marcos wishes he had had his camera on him at all time.

More uncomfortable silence. The length of the silence must be carefully controlled, like a stroll over the fine line between being a fearless jokester and an incorrigible asshole.

MK: Jajaja! Just kidding. I’m from Mexico.

Oh, the look on his/her face… I wish I always had a camera on me. If the new acquaintance recovers from this one, you know you’ve made a new friend.