Easiest Way to Handle Multiple View Styles?

[eluser]gtech[/eluser]
If the template is select by the user,
the easiest way to store and retrieve variables that are available across page requests is to use the session library, this is well documented in the CI documentation.

if the template is selected by a permanent config value then take a look at the config class:
[url="http://ellislab.com/codeigniter/user-guide/libraries/config.html"]http://ellislab.com/codeigniter/user-guide/libraries/config.html[/url]
You can add your own variables to the config/config.php file