Some created their own versions of the official "rules" to play as an offshoot, such as placing any fines into the middle of the game board instead of giving it back to the bank, and any player landing on "Free Parking" received all the accumulated money. Kind of like a Monopoly Lottery.
In the 1980s, two new companies appeared on the scene offering localized or customized versions of Monopoly. Late For The Sky Production Company began in 1984. Thier first game was MIAMIOPOLY, based on Miami University in Oxford, Ohio. The company founder and president was a 1980 graduate of Miami University and her time spent there served as the inspiration for the first game. The title list soon spread to around 80 major U.S. colleges. Each game is a walk around a specific university and the board spaces are the campus buildings, local businesses and traditions that are special to that school. Today, they produce product lines that include "-opoly" games for nearly sixty major colleges and universities in the United States, and the "City in a Box" games, localized for major U.S. cities. They also have a line of specialty games, and produce custom games for other themes.
USAopoly is another Monopoly variation that came on the scene in 1994. Today they are a leading developer and manufacturer of board games and puzzles. They have been producing the world’s most beloved games “with a twist,” under license from Hasbro, since their beginnings. Many games are themed on specific characters, movies, or events, and their partners include multi-million dollar brands and licensors such as Disney, Nintendo, Microsoft, Cartoon Network, M&M’s, BBC and Warner Bros.
In addition, the Hasbro owned Monopoly continues to expand into its own customized versions of Monopoly, one of the latest being a version of the popular movie "Frozen".
This has created hundreds of variations of Monopoly, and today a consumer can find a game that matches their - or their child's - unique interests. Love dogs? There's a "Dog-Opoly" Game. In the Army? There was an "Army" version. Are you a Fireman? Yep...there's a Firefighters version. The variety has created a great demand for many of these games that were produced in limited quantities, and are no longer produced. For instance, the Firefighters Monopoly Game, now long out of production, is now bringing a couple hundred bucks on Amazon.