I thought I'd mention a couple of "Hot Spots" where anyone can anyone can connect to Free Wireless Internet.
Athens Center/Downtown(http://www.athenswifi.gr/en/)
24/24hrs, all you need to do is connect to the 'athenswifi' wireless network with your laptop,once you open your browser a code will appear which you will have to type,this is only for the 1st time you try to connect.After that you can surf freely!
Free Wifi also available:
Syntagma Square
Thiseio (9am-5pm)
Kotzia Square
Piraeus Port
Athens University( for employees and students of the University- password needed -can be obtained by contacting University staff)
Gkazi/Technopolis
Will add more if I find, if anyone knows any other Wifi Free spots pls add!