Originally Posted by
FLYMSY
Get an unlocked GSM phone, go to any phone shop in Germany, buy a pre-paid sim card from the carrier of your choice (I use a T-Mobile pay-as-you-go sim card), put it in the sim card holder of the phone and you're ready to go. Top up the card as needed. It's a very easy process.
+1 Another vote for using a T-Mobile SIM card in an unlocked GSM phone. I originally bought my SIM at the T-Mobile store in the TXL shopping area three or four years ago, and I load more minutes over the Internet, no matter whether I am in Germany or elsewhere (I recently re-loaded over the 'Net in the UK and from the U.S.).