1. Gardens (yards) are very small. If a small US yard is a postage stamp, think of those tiny 1 cent stamps you use every year when the postage goes up and you forgot to get stamps and you are digging around until you finally find the Christmas stamps from 2009. That's an Irish yard- even in hunks of the countryside where the houses probably don't HAVE to be stuck quite so close together but it is in keeping with the traditional village development style.
2. The small gardens mean that I almost never hear a lawnmower. This puzzled me since they do have tended grass until one evening I saw several people using plug in lawn mowers and leaf blowers- those babies are soooo much quieter. One lady, with even less grass, was on her hands and knees with hedge clippers.
3. The street lamps in Dublin have several different designs related to Irish culture. They are all really lovely and it's fun to try to spot the different designs. I haven't been able to find much information but these are some that I've managed to get decent pictures of.
4. If you want to get someone's attention say "Sorry." Trying "Excuse me," "pardon," or "Ma'am" is completely pointless. A quickly muttered, under the breath, "sorry" gets instant attention.
5. The windows are different. You do see the sash type that are generally found in American homes, mostly in the older buildings, but most newer homes and many office and apartment buildings have tilt windows.
6. Electricity is SCARY! :-) You will never find a light switch in a bathroom. When asked about it, our Irish friends have all looked askance at our crazy American ways and explained it's for safety reasons, obviously. Electric on-demand water heaters in the shower stall with you are totally fine, though.
7. All sockets have individual on/off switches. We accidentally turned off the refrigerator one day but noticed before any harm was done.
8. Hotels provide mammoth towels and handtowels but no washcloths.
9. Eggs are unrefrigerated in grocery stores. I'm ok with the general concept- it takes eggs quite a while to go bad, even at room temp, but I would feel better about it if I knew how long they had been at the grocery.
10. The Irish speak Irish and the Scottish speak Gaelic. According to wikipedia- the Irish introduced Irish to the Scots and they are still quite similar. It doesn't have a "th" sound so a fair number of people in Ireland will say "tree" rather than "three" when they aren't thinking about being clear for the poor, befuddled American listener. When we visited the children's school, I was politely corrected when I asked about how much we would be expected to help with their Gaelic lessons. :-)