If you have flexible working hours then you can avoid the traffic. I leave (driving) Celbridge at 6.20 and am sitting at my desk in Donnybrook by 7.00, 6.55 this morning!! I then leave at 3.30 and I'm home by 4.30. That's going by the N4, M50 etc - there are probably quicker ways but as this is a short term thing for me I haven't checked them out.