Different themes based on URL

You can easily make custom page templates and custom category templates. For a category you would just need to copy over the category.php from one theme(summer) to the active theme(winter) and name it category-id.php where id is the numerical id of the category. You also need to copy across any relevant css, images and javascript and adjust any links accordingly.

I needed this exact thing recently for my site and couldn’t find anything. So I modified another plugin that switched theme based on dns settings. I uploaded it here for anyone else that might be interested.

http://www.mobilesentience.com/apps/oss/virtual-theme/