Tatler Jack's, Killarney
We wandered into Tatler Jack's by chance (Ellen left the tour guide I got her back in Dublin), and it was a good find. Good Guinness, fast service, and as we often found in Ireland, a great cross-section of the population (young, old, professionals, pensioners...).
There was live music which was lively as well. Probably get tons of business during tourist season as it was pretty full even during the off season.