| Ashley |
Applewhite | Deputy editor of the student newspaper; Mary's next-door neighbor. |
| Rocky |
Balboa | Fictional boxer. |
| Jean |
Bartik | One of ENIAC's creators. |
| Sister |
Beatrice | Name in the tomb. |
| Mrs. |
Beckenbauer | Regal owner. Aka: The Sea Hag |
| Tyler |
Bell | Senior student helping the boys. |
| Fran |
Bilas | One of ENIAC's creators. |
| Officer |
Blaszkiewicz | Police officer called to Billy's mother. |
| Sharon |
Boyd | Mary's former best friend. |
| Alfred |
Boyle | Billy's friend. Aka: Alf |
| Christie |
Brinkley | Model. |
| Dr. |
Brooks | Contest judge; Mulligan's substitute. |
| Jack |
Camaro | Guy who scammed the boys. |
| Mark |
Cenry | Whiz kid game designer hired by Atari. |
| Mr. |
Crenshaw | Pharmacy owner. |
| Mrs. |
Durham | Zelinsky's customer. |
| Sister |
Ellen | Nun at St. Agatha's. |
| Jerry |
Falwell | American televangelist. |
| Senora |
Fernandez | Teacher; Tyler's relationship. |
| Dante |
Gagliano | Detective. |
| Bernard |
Goetz | Suspect for shooting four kids. |
| Ms. |
Grecco | Billy's typing teacher. |
| Margaret |
Hamilton | Well-known programmer. |
| Gary |
Hart | Presidential candidate. |
| Mr. |
Hibble | School principal. Aka: The Duke |
| T.J. |
Hooker | TV character. |
| Zhang |
Hsu | Contest winner. |
| Billy |
Joel | American singer. |
| Freddy |
Krueger | Fictional horror character. |
| Chadwick |
Melon | Captain of the basketball team. |
| Reverend |
Mother | St. Agatha's headmistress. |
| Fletcher |
Mulligan | Contest judge; owner of Digital Arts. |
| Mr. |
Nanette | Boss of Billy's mother. |
| Donna |
Rice | Gary Hart's mistress. |
| Lynn |
Scott | Works at Video City. |
| Howard |
Stern | American media personality. |
| Marlyn |
Wescoff | One of ENIAC's creators. |
| Vanna |
White | Wheel of Fortune host, Playboy model. |
| Roberta |
Williams | Creator of King's Quest. |
| Sal |
Zelinsky | Store owner who sold Vanna White's Playboy magazine. |
| Mary |
Zelinsky | Programming geek; Zelinsky's daughter. |
| Billy |
| Protagonist, computer nerd. Aka: William Marvin |
| Clark |
| Billy's friend. |
| Gretchen |
| Billy's aunt. |
| Hooper |
| Gagliano's partner. |
| Mary |
| Lynn's co-worker. |
| Rene |
| Tyler's cousin. |
| Schwarzenneger |
| Zelinsky's dog. |
| Tack |
| Police officer. Aka: Tackleberry |
