Usergroup Selecter Feature

[NoKSouLz]

Basically i run a gaming forum and were expanding to different games.

The idea is to have the same sort of theme except different sections and background image for each game.

The way i thought of doing it, would be to setup 4 usergroups that display the different sections for each game. They also have a default set theme which changes the users theme to suit the game.

Is there a way to make a dropdown menu to select a game which changes the users usergroup to the games usergroup they have selected?

Thanks