Depends what sort of tat you're looking for IMO

Admittedly, I do a mileage run when my Guinness mug breaks (I have a nice large one that fits... amazingly my mug breaks once a year. Funny that). That and a box of Lily O'Brian choccies (although to be honest, I could probably get both in my local shops if I feel the urge).

As long as you don't have to go to the A or D gates, Dublin Airport is agreeable...

Otherwise... it's the same tat as you'll find anywhere in Dublin itself...