At the beginning of their musical careers, producers were wary of the strong accent prevalent in their songs. Rumor has it, Charlie and Craig refused to tone down their Scottish brogue and, consequently, wrote the song, Throw the R Away.
They also made big sucess in their song 'I'm On My Way', which featured in the Shrek Soundtrack (2001)
From Wikipedia:The Proclaimers are a Scottish band composed of identical twin brothers, Charlie and Craig Reid (born 5 March, 1962, in Leith, Scotland). They are best known for the songs "Letter from America", "I'm On My Way", Sunshine On Leith, and "I'm Gonna Be (500 Miles)".