Monopoly is one of the best games ever invented, in my opinion but even it can use some additional excitement now and then. Maybe using some of the Monopoly Home Rules would help liven things up a bit. Here's an example of what you'll find:
Start At Corners
Rule: Players put their tokens at the four corners of the board rather than Go as their starting positions. The player on "Go to Jail" does not. Players should be spread evenly to all the corners, and which player starts at which corner should be determined randomly.
Reason: By starting in different locations, the players are less likely to land on properties already owned by players who went before them.
Click this link to learn more Monopoly Home Rules: http://wiki.playagaingames.com/tiki-index.php?page=MonopolyHomeRules.