I find code-switching rather fabulously intriguing, myself.
A few years ago, I was on a chairlift drinking a can of Budweiser with a ski bum friend who lives out of a truck. We might have had a belching contest. Within 48 hr, I was having brunch at the home of two blue-blazered scholarly types (PhDs, think tank fellows, corporate board directors -- basically a couple who has attained the highest levels of the US corporate, government, and quasi-government ladders), and actually sort of carrying on a conversation. But not like theirs ... they are the type who speak in fully parsed and punctuated paragraphs, somehow formed in the brain before passing the lips. It was really strange. But cool.