The Mainframe is a film released in 1998 produced by Love Media with advertisments shown in Grand Theft Auto: Liberty City Stories and mentioned in Grand Theft Auto V. It is a clear parody of The Matrix, though The Matrix technically did not premiere until 1999. The movie poster shows Alan Crawford, Barbara Schternvart and pedestrians from Grand Theft Auto: San Andreas. Jock Cranley is one of the actors in this movie.
The movie is about five teens who take LSD and discover the 'truth'. They actually live in a computer. Quotes from the movie include
"What will it be? Yes, or no? 1 or 0?"
"Ahh! Your face is a big pixel!"
It is rated PS (Pretty Stupid).