I've spent some very happy days on Inisheer, the smallest of the Aran Islands, in Ireland's Galway Bay. Now you can take a ferry from Doolin to Inisheer as well. Check out the website from these fine folks. In addition to ferry (and ferry booking info), there's also some information on the island too:
Link: Aran Islands by Ferry - Daily ferry from Doolin to Aran Islands.
