The song that Lincoln Wineberg sings and claims to have made up himself is actually based on the 1912 song "They all walk the wibbly-wobbly walk" written and composed by Paul Pelham and J.P.Long, and originally performed by music hall comedian Mark Sheridan.
"Shok", the short story from the British magazine "2000AD" that the film is based on, was about Mike, a Strato-Bat Pilot, who buys the head of a Shok trooper robot as a gift for his artist girlfriend Lyn who then uses it for her metalwork. The Shok trooper robot reactivates and goes on a rampage in Lyn's apartment.
For his appearance as the cabbie, Lemmy was equipped with a bottle of Scotch and a genuine Magnum revolver. He emptied the bottle and drew the gun out from his shoulder holster. It slipped his hand and sank to the river. Divers were sent to recover it, but they were unsuccessful.
Richard Stanley originally wanted Bill Paxton as Mo and Jeffrey Combs as Shades. Paxton was enthusiastic about the script, but Miramax and Palace Pictures did not know anything about him, so they didn't contact his agent, and Paxton signed on for Navy Seals (1990) instead. Combs couldn't be cast because British union rules allowed them to hire only two Americans.
The nomad who unearths the MARK-13 robot is played by Carl McCoy, lead singer of the goth rock band Fields of the Nephilim, for whom Richard Stanley had previously directed two music videos and designed an album cover. According to him, McCoy's character in "Hardware" is basically the same as it was in the Nephilim work. The character, then titled Preacher Man, had a prostethic hand, yellow contact lenses and wore an old black coat with a cowboy hat.
In the original theatrical release, the 2000AD magazine short story "Shok", was not given a "Based on" credit, as the story of the film was based on the short story. On the 2009 DVD release, "Shok" was credited, after the end of the end credits, acknowledging the original story that inspired the film.
Richard Stanley wrote a sequel to the film, called "Hardware II: Ground Zero", and tried to get the project off the ground for a few years. The sequel would have been somewhat different than the original film, closer to a western, with a much larger scale. The project stalled because the rights to the original movie are split between several parties (among them Miramax and producer Paul Trijbits).
When Jill turns on the television after looking in the fridge, the first channel she is on shows a black and white video that is actual footage from World War 2 of German soldiers shooting Jewish prisoners inside a pit.
Mo says to Alvy "You use to be an elf, didn't you?" Mark Northover (Alvy) once tried to get a job as an elf at Santa's workshop at a mall. But, the mall's owners didn't give him the job, because they felt he would scare the children.
The Nomad, played by Carl McCoy, was originally scripted to appear in Jill's dream sequence in the middle of the film. The scene wasn't shot because of the actress' illness during the filming in the desert.
Fields of Nephilim (Carl McCoy's band) was in talks to contribute to the film's soundtrack. This didn't happen since the production company, Palace Pictures, was tied in with Virgin. They preferred the soundtrack to be made by 'in-house' artists.
John Lydon, the frontman of Public Image Limited, was rumored to be in talks to provide the nasal squeak for Angry Bob, the insane DJ of W.A.R. Radio Channel. The part eventually went to Iggy Pop, yet Lydon is still heard in the film's soundtrack in the PIL track "Order of Death". Ironically enough, the cast listing in the back cover of the Japanese laserdisc credits Lydon for the part.
When Shades is preparing to jump past the malfunctioning slide doors, a flyer of Mona Lisa (1986) can be seen in the background. Both this movie and Mona Lisa were produced by Stephen Woolley and Nik Powell.
When the film was released in New Zealand on the big screen and on VHS in 1990, it was given the R18 rating for it's graphic violence, sex and bad language. But, when the film was released on DVD in 2011, it was re-rated R16.
The trivia items below may give away important plot points.
According to Stanley, Vernon's death was supposed to be one of the movie's nastiest moments: he was originally meant to get shot in the balls, then cut up with a chainsaw while he was still alive. Paul McKenzie had a page in the script of screaming and begging as his spine was severed so he couldn't move, beseeching Jill to help him, with the droid basically using him as bait to get her. The scene wasn't shot because it would have taken two days and the production was at the end of the schedule, so it was decided to shoot Vernon in the head. The scene was supposed to make Chief's comment after the chess match ["Machines don't understand sacrifice... and neither do morons!"] foreshadowing of Vernon's fate.