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 prosthetic hand, yellow contact lenses and wore an old black coat with a cowboy hat.
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.
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 wanted to use stop-motion animation for the Mark-13, but was unable to do so because there wasn't enough time and money to use this particular technique.