The Symbol Today?
The Wheel of Dharma
From The Teachings of Buddha

My brother-in-law, whom knows I am into this wagon wheel symbol sent me some interesting photos from his hotel room in Singapore. It is certain that this is a very similar symbol, to that used by the early Christians and Followers of Christ. One could speculate on this, however we must keep in mind that a circle was a common, powerful symbol, used in many forms of non-verbal communication. One just has to look skyward to see powerful, mysterious, beautiful circle symbols, such as stars, the moon or the sun.

"The Dharmacakra symbol has the form of a wheel with eight or more spokes (sometimes 24 spokes representing the solar cycle). It is one of the oldest Buddhist symbols, found in Indian art from the time of the Buddhist king A?oka, and used by all Buddhist nations ever since. One version of the symbol, taken from the capital of a pillar erected by A?oka, is found on the flag of the modern state of India. In its simplest form, it is recognized globally as a symbol for Buddhism." source:
http://en.wikipedia.org/wiki/Dharmacakra