I grew up in Boston, and many of my friends and teachers had Boston accents. I always wanted one, and wondered why I never acquired one (or simply couldn't). I can spot an authentic one instantly, and I feel a real sense of familiarity and a bit of nostalgia when I hear someone speak with a Boston accent.
I love regional accents, and I can usually identify them. I can often even tell the language of origin for a person who speaks English as a second language. I once guessed (correctly) the language of origin of a person I met in our local library many years ago. Her English had a vaguely Slavic tinge to it, but it reminded me vaguely of the way people I knew from former Yugoslavia spoke German. Then there was this bit of French in the way she pronounced the letter "D." I guessed that her first language was Serbo-Croatian, but that she might have learned English from someone who was French. I was right on both counts: she was from Serbia, and her family moved to Toronto when she was a teenager. It kind of freaked her out.
It occurred to me that with all the people I knew when I was growing up in Boston, and later when I lived there as an adult, I never met an African American person with a Boston Accent. While searching online to see whether anyone else noticed this linguistic phenomenon, I came across the "Worldwide Accent Project", and have decided to contribute my accent-less voice to the project.