My first idea is of a web site that will provide users the ability to send SMS messages to Greek mobiles, at low rates (or free if the service becomes self-sustainable).
Hmm, that's an idea you have there. I don't have any ideas. If you don't mind this post being here(can be updated) to see responses or standpoints from sms services in Greece to see which ones have any potential interest in accepting
BTC.
I don't find it worth the effort to contact viva.gr's sms service for personal reasons.
[Service, date of inquiry,comment]
Got a reply:
time4sms.gr, Feb 10 2013, They have not stated any view on Bitcoin at all, they didn't answer on that point. They said "We require a Greek cellphone number and we accept only ".

No time for time4sms.
'No reply yet':
bulker.gr, Feb 10 2013, Asking about if I am required to have a Greek phone number to register(and test out their service for 5 free sms messages) and if they accept Bitcoin.
opensms.gr, Feb 10 2013, Asking if I am required to have a Greek phone number to register and what they think or feel about Bitcoin.
txt4coins.net is the only SMS service that I know that supports Bitcoin purchases of SMS'es. Still waiting for a reply from bulker.