Here's a tune popular among some fiddle players in Donegal. I'm not sure whether it is unpopular among everyone else in that county but I'll maybe avoid playing it there just to be on the safe side.
There is a version of it here: http://thesession.org/tunes/11250 taken down from the fiddle playing of Vincent Campbell (presumably one of the Donegal fiddle players amongst whom this tune is popular). I've also heard a recording of John Doherty playing it and I first learned it from another fiddle player, i.e. Paul O'Shaughnessy who has a keen awarness of the Donegal fiddle zeitgeist.