The former Byzantine areas were obviously once culturally very much like Greeks. At one point, Afghanistan was also culturally very Greek as well (Greco-Bactrian kingdom, Alexander the Great era). However, the only thing Afghanistan notably shares cultural similarities with Greeks in today is the Khattak sword dance. The "Macedonian hat" was also inspired by the Afghan hat:
http://media.gettyimages.com/photos/...7874?s=594x594
Egypt also shared many cultural elements with Greece.
However, today, it seems that Italy, Iberia, the Balkans (obviously), and the Christian Levant share the most cultural elements with the Greeks.