If you've got a few hours in Dublin with nothing to do, I heartily recommend the Irish-Jewish Museum.
Twenty minutes' walk south of the Liffey River, the Museum was once the synagogue in the center of Jewish life in Dublin. Today it offers a multitude of archives, artifacts, and informative and entertaining displays on this little known part of Irish history. The ground floor contains a large exhibit on Irish-Judaism, beginning with history, and branching out to include such topics as youth groups, prominent people, different stories of various communities, daily life, and so on. Next to the exhibit hall lies a well-stocked kitchen as it might have looked in a Jewish home in Dublin decades ago. In fact, it was once the actual kitchen of the museum's caretaker.
Upstairs, the original synagogue seems almost unchanged (if you ignore the very museum-like displays of religious articles in the back!) If a service had to be conducted there, the room would soon be ready to go.
The overall atmosphere is quiet, relaxed, and friendly. The building itself is old, small, and comforting; it's easy to imagine the gatherings that once took place there. The curators (whose Dublin accents mix interestingly with Jewish intonations) act more like storytellers than gallery supervisors. When I was there, one of them went out of his way to give me a proper introduction to the story of the Irish Jews, reading aloud in Gaelic the passage from the Annals of Innisfallen which record the first arrival of Jews in Ireland (it's common for Irish Jews to be trilingual: English, Gaelic, Hebrew!)
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