I have explored options and I think I will go with CALL IN EUROPE for 2 weeks in Germany in June. I like the idea that I get billed later and don't have to keep pre-paying. The rates look good too. I know that I could wait until I get to Germany but our time is limited and I don't want to go searching for a phone and SIM card after I get there. I can get a cheap phone with good reviews (NOKIA 1208) and a SIM card for $58 ($29 each) > http://www.callineurope.com/
Any thoughts?