The Tibetan Tongue Sticking:
Yes, sticking your tongue out to someone in the region of Tibet shows a sign of respect. The origin ir believed to have derived from the Tibetan King, Lang Darma, known for his cruelty and black tongue. People fear that he may reincarnate and Tibetans greet one another by sticking out their tongues demonstrating that they do not have black tongues.
Touching Feet in India:
This is still very common amongst cultures in India to touch the feet of elders and teachers a sign of respect. It is more like a sacred greeting in Hindus and in a way seek their blessings in return. In return, elders place their hand on their head or back of the blessing seeker.
Yes and No in Greece:
In the United States, as well as in the majority of the countries, shaking your head from left to right means no and up and down means yes. In Greece they mean "yes" by tilting their head first to the left and then the right. When they mean "no" they tilt the head up and back. Other countries with similar tactics include: Bulgaria, Albania, Saudi Arabia and Iran.
Eye Contact in Middle East:
In many Middle-Eastern cultures, intense eye contact between same genders is often a sign of trust and sincerity. This is not the case with opposing genders. Eye contact between different genders, anything more than a brief eye-contact is considered inappropriate.
Pointing in Asia:
In the western world, we often point at things to help explain a point. However in many Asian countries, especially China, pointing with the forefinger is considered rude. An alternative way is to gesticulate towards the "point of interest" with an open palm that faces upwards.
In case you are traveling any time soon, check out these websites! It is important to know what is acceptable, non-acceptable and required before landing in a foreign country. Nonverbal Communication Across Different Cultures and Cross Cultural Communication Tips.