Donna provided an excellent summary of her trip - thanks so much!
Got our first bill - Citibank charged $5 per overseas ATM transaction, plus the usual finance charges. For credit card purchases, Citibank charged an additional 2% on top of the 1% Interbank (Mastercard) currency exchange fee. I heard that if I had used my MBNA or CapitalOne card, I could have avoided the 2% charged by Citibank and other "major" banks.
As an American Express card holder, I was able to purchase travellers cheques in Euros. They worked great in Finland and the Low Countries, but caused some confusion in Tallinn, Sweden, Norway, and Denmark. We had to find a cash exchange office (good luck trying to find one on a Sunday!), incurring a fee ranging from $2-5 to obtain the local currency.
At the end of the cruise, the ship was offering to exchange Euros for Dollars on a one-to-one basis as a "courtesy" to its passengers. I offered to take the hated Euros off their hands at an identical rate of exchange, but I was rebuffed. :-)