Mexico City is an AMAZING taco city.
The master of all Latin Food bloggers, Bill Esparza, has a BLOG full of info about eating there.
I tend to stick to the trendy areas of La Condesa and La Roma. Super hip.
I was taken by a couple of awesome taco superfreaks to a DRIVE-IN taco spot.
It was crazy delicious and crazy fun. If you visit, you must put this place on your list. Maybe taxis go there too, I don't really know.