Although he was lived in Israel for 40 years this IDF Colonel still has a strong Scottish accent when he speaks in English. He is one of the main media spokespersons for the IDF. Link. MSN
My accent changed radically when I was in the US. To this day I still say, "garbage", "sweater", "truck", etc. I also write using American spellings, because I just got used to it, and I did so much work with Americans that I set up all my systems to use US English. Today I'm mostly mistook for an Australian. Still, anything was better than Essex.
When in the US I noted that both Scottish and Irish accents are very slow to fade. If ever. I worked with Germans, French, and their accents would get whittled away. But the Scottish and Irish seemed to hold on to it. I'm generalizing, of course.
David Byrne of The Talking Heads was born in Scotland though - so that ridicules my own conclusion.