TechCrunch found out that Anderson used to be a teenage hacker in the 1980s. It turns out he has a pretty colorful history, when Tom was only 14 years old he was the leader of an early blackhat hacker group. He and his friends hacked the Chase Manhattan Bank and were subject to one of the largest FBI raids in California history:
Now we’ve learned a much more colorful part of Anderson’s history: In 1985, when he was fourteen and in high school in Escondido, California, Anderson was subject to one of the largest FBI raids in California history after hacking into a Chase Manhattan Bank computer system and subsequently showing his friends how to do it. He was never arrested because he was a minor, but the FBI confiscated all of his computer equipment and some newspaper accounts of the incident stated incorrectly (see image below from a 1986 LA Times story) that he was “convicted in federal court of computer hacking and placed on probation” (the statements were corrected in subsequent articles). Anderson used the hacker name “Lord Flathead."
Anderson, using the name Lord Flathead, was a computer hacker at least since he was 13 years old, which is just about the time the movie WarGames came out in theaters. Like David Lightman in WarGames (played by Mathew Broderick), Anderson was able to hack into computer systems by simply figuring out the right phone number (this was called “war dialing” and was done with the help of a simple computer program that dialed sequential phone numbers until it received a modem response, signaling a computer system on the other end, usually a UNIX mainframe that often had a default password or no password at all). Once you were past the password security, you often had deep access to whatever system you had called.