Been to Greece last week and bought Cosmote (because of the widest 3G coverage).
Paid €5 for the simcard, which includes €1 and then €1/month for the following 4 months (finally making the simcard free).
I needed to show my passport and the salesman was so kind to call the customer service for me from his phone to make them change the 1314-menu (which is free in Greece) to English
Activating the 60MB package wasn't a problem. Internet worked very well.
What didn't work though is checking how much MB's were left to be used. To do this, one should send an SMS "INFO" to 1313, according to:
COSMOTE: CIOTP for prepaid Customers
When I did so I received the following message back: "Η ΥΠHPEΣIA ΠOY ZHTHΣATE ΔEN YΠAPXEI", using Google Translate I can't really figure out what it means
Is it true there is no *101# - like code to check the account status in Cosmote? I found the only way to check it is by sending "YP" and "LIXI" to 1314 which is free in Greece, but is charged for when in roaming...
Also, where do I find information about extending the validity of the card? Mine is valid until april 2012. How much does one need to recharge to extend this? (I couldn't find this information on their website).