Through the centuries teachers of prophecy have attempted to fit many names into 666. Nero Caesar was a popular choice during the early centuries of Christian thought. Hitler was certainly a character that many sought to tie to this prophecy. Some have even tried to associate this number with the name Ellen Gould White even though applying 666 to a person also requires that individual to be a "man."
Among the more creative suggestions was the recent association of the number with Ronald Wilson Reagan, because he had six letters in each of his three names. After leaving the presidency, he moved to a home in Los Angeles. Evidently the numerology bothered him enough that he had the address changed from 666 St Cloud Drive to 668!
One recent favorite is the allegation that 666 appears on some international product codes. Since this related to buying and selling (Rev. 13:16, 17), some think it significant. As far as I know, however, no one is talking about printing these codes on the forehead or the hand yet.
One California resident fought in court to prevent his daughter from being assigned a Social Security number. He somehow had the impression that Social Security numbers were associated with the 6-6-6. Since a couple each has a Social Security number of nine digits, together they have 18, which totals 6+6+6! Do you see how creative this gets? (Of course, the biblical number is six hundred sixty-six, not six plus six.)
If we adapt the rules to make names conform (say multiply by seven, add four, then divide by three) we can eventually make any name fit 666. Bible scholars, scientists, and labor unions have all surfaced as candidates for the antichrist. Some have even speculated about the children's TV character Barney. If one adds up the Roman numerals of "Cute Purple Dinosaur" you get a total of 666. Hopefully, someone did that one as a joke!
More seriously, through the centuries many Christians suffering intense persecution supposed that they were experiencing the final tribulation before the Second Coming. It is not surprising that they wondered if Stalin, Hitler, or some Muslim ruler not be the final antichrist. While they may have been wrong in thinking they were the last generation, they gained courage from grasping the larger principles of the book of Revelation. And in quality, if not in time, they tested in part the final struggle with the forces of evil.
Lord, I pray that speculation will never distract me from the challenge that Scripture presents to my way of life. Help me to be true to the realities of Your Word.