I've cracked the trip to Dublin to the National Library for a research day. Drive to Heuston Station and park there, only 7 euro for the day, Luas to Abbey St and walk from there. Cheapest, quick, includes exercise.
The Luas from Heuston at 9 in the morning is usually packed so it's standing for the short ride to Abbey St. On Tuesday a little later than 9 it wasn't packed but all the seats were occupied so I stood. Just in front of me a youth turned round, looked at me, got up and offered me the seat. Shock! What to do? I just sat down.
Ah well, old age has some compensations.