Happily, pay-as-you-go phone service is rather better in Germany than in the US; depending on how often you plan to get back to Europe, you could probably find something reasonably priced for your purposes. (Yes, I do miss competitively-priced services; why do you ask? *sigh*) GSM-or-better networks, so there's also the option of getting a European SIM card if your phone is GSM-family rather than CDMA. Have a great time!