An Episcopal priest I was very good friends with told me it was symbolic of Nero.
The early Christians were very interested in numerology, and when the rules of numerology are applied to the letters in Nero the result is 666 (sometimes 616)
The text is very specific that it is the number of a man, interpretation calls for wisdom, and that it is the result of a calculation.
I tend to believe that this all adds up the the Nero interpretation being more probable that any of the others.
I believe it represents Nero AND the coming anti-Christ. Certain patterns seem to me to repeat in the Bible, especially with respect to big events and the rise and (self-inflicted by turning from God) of nations.
Preterism