The foundation of a Game Show is something called a "lock out." Simply put it is an electronic system that indicates the first person to press a button with light and sound, and at the same time lock out the other players. Outside of the lock out, the way you assemble players, the questions you ask and the rules you use end up creating the actual Game Show.
The possibilities are endless and you can let your imagination be your guide to create the best group activity you have ever had.
Some simple ideas could be Corporate Survivor, Millionare, Name That Tune, Family Feud or almost any game you can imagine.