These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
An advertisement for Fuji Film is seen in the background of one scene. The film's creators couldn't have predicted that analog photography would be all but killed off by digital photography long before 2084 (the year in which the movie is set).
Special Effects Failure: When Richter falls off the elevator after getting his arms severed, if you look carefully, you can see that the stuntman just stuffed his arms underneath his shirt.
When Quaid fights Harry's goons off and knocks them against the concrete wall behind him, the wall visibly shakes.
As seen on the original VHS releases of Johnny Handsome, The Fabulous Baker Boys, and Music Box, during the teaser trailer, when shown in 4:3, the digital Arnold head starts to become uncontrollably shaky as it's about to pass the top edge of the 4:3 area, and the shape looks completely unrecognizable as it disappears over the top edge.