The book that 007 picks up from the Cuban sleeper, along with a revolver, is "A Field Guide to Birds of the West Indies", written by James Bond. Ian Fleming, an avid birdwatcher, named Bond after the author.
The use of hovercraft by the North Korean Army to circumvent the minefields of the Demilitarized Zone is entirely fictional. However, the science show MythBusters (2003) tested the concept and found it plausible.
Pierce Brosnan disliked the gadgets and overblown effects of this movie. He suggested to the producers that the franchise go back to its more low-key, darker roots. Coincidentally, after Brosnan left, the next Bond movie was the low key and darker Casino Royale (2006), which was stripped of gadgets and extravagant visual effects and stunts.
For the sword fight, the filmmakers decreased the film speed to make it look as if the actors were moving faster than they actually were.
Deborah Moore: The daughter of Sir Roger Moore makes a brief appearance as a flight attendant on the British Airways flight.
Madonna: As Verity, the fencing instructor, making this the first James Bond movie to feature a cameo by the performer who sings the theme song. Her uncredited cameo was the final scene shot during principal photography. When James Bond introduces himself to Gustav before they fight, Madonna was originally to introduce him with the catchphrase, "Bond. James Bond." However, it was later decided that fans would prefer the line coming from Pierce Brosnan.
Michael G. Wilson: As General Chandler, this is Wilson's first credited cameo performance in a James Bond movie. He can also be seen in an uncredited cameo as a man leaning against a car in Cuba. Wilson has made an uncredited cameo in every EON Productions Bond movie since La spia che mi amava (1977), as well as an early one in Agente 007 - Missione Goldfinger (1964). His first screen credit for acting though, was not for this movie, but for All the Way Home (1971).