Elvis units:
Set the system date to January 8th. All King-type units will become Elvis.
High-efficiency Worker Governments:
When starting the game, you are in the Government Despotism. Your workers are so slow that it is annoying. Quickly research the lowest two branches of the tree in Ancient World to get the Monarchy Government. Your worker speed doubles, and you can Hurry anything except a Small or Great Wonder by spending gold, not population. Play normally until you can get the Democracy Government in the Middle Ages era. Worker speed goes up 1.5 times. What used to take you six rounds now only requires four. After that, play normally until you get to the Modern World. There is no reason to choose Communism, except for Police Stations (which you do not need to be Communist to build). This means you can actually not research Communism. Instead, choose Fascism Government. It speeds your workers up again. What takes three rounds in Democracy only takes two in Fascism. This is the fastest that you can get. The speed ratings are as follows.
??? Despotism: 50%
??? Monarchy: 100%
??? Democracy: 150%
??? Fascism: 200%
Most of the others are 100% speed. Also, Monarchy is the easiest to get.