Come to think of it, the Boston accent is probably the Cockney accent of the United States.

I'd have to say the Brooklyn accent ("you godda problem wit dat?") is far more spiritually in tune with an English cockey accent then the standard Boston middle-class "pahk the cah in Hahvahd yahd" accent. (My father is from Brooklyn and my mother is from Boston. I grew up hearing both accents regularly.) There's a completely separate upscale Boston accent, famously spoken by JFK and there's also the "southie" Boston accent as heard from Matt Damon and Ben Affleck in "Good Will Hunting". Southies are in another world.

Probably my favorite of regional American accents has to be the Minnesota "ya sure, you betcha" Scandinavian-derived accent as heard in "Fargo". That's just absolutely addictive to speak, although I have to admire the Cajun dialect as well. I say "dialect" because they toss in French words more often than Jews from New York mix Yiddish into their regular speech. There's a Cajun DJ who plays Zydeco here early on Saturday mornings, and I can barely understand a word he says.