New York Times British and Irish dialects test - Where are you from?Watch
Now although I've been living in Northern Ireland since I was 14, I previously lived in Ipswich and my accent hasn't changed, so I took the test and got:
Pretty accurate. Although I've never been to Portsmouth.
They asked you questions like "When you say the words Food and Good do they rhyme?" to which if you respond yes they'll immediately place you up in Scotland or Northern Ireland.
Just did all 96 questions and it is dark red around the Birmingham/ Midlands area so I would say this is quite impressively accurate and am impressed.