I was wondering if anyone had any experience w/ cheap ways to to Ireland from the continent. Are the ferries any cheaper than flights? I don't have a railpass and would like to see Ireland while I am in Europe, but would need to be able to justify the cost. Thanks!
Use a budget airline search engine like www.whichbudget.com or www.skyscanner.net. Even though you'll be flying to Dublin, enter Dublin as your departure airport and then check the destination airports--and airlines--listed under France and Spain.
You can do the same for Shannon, but you'll have fewer choices.