Mumbai, India

It's pandemonium as taxis compete for precious pavement with tuk-tuks, buses, bicycles, rickshaws, trucks, pedestrians, camels and the occasional elephant. You'll watch in awe as traffic utterly disregards traffic signals and centerlines while your ears are assaulted by Hindi pop music whose pounding beat can't mask drivers' apparently mandatory use of the horn for echolocation. You won't be involved in a serious accident, however, since you'll never exceed 15 mph while you navigate through the choking smog.

An alternative: Call Cool Cabs. They cost 40 percent more than regular taxis, but that's still not much, and you're guaranteed to get air conditioning, an absolute must.