In your blog, you may cover various categories from Tech to Fun stuffs.

It would be good if you can give a different look and feel for the categories reflecting its type.Reflecting a look which is related to the category helps reader to get a feel as if they switched over to some other site but in fact they are in your same site but only the looks had changed.Coupled with this if you use Category to Sub Domain Converter Plugin it will give an all new feel will also be easy for the user to remember the URL easily.

Here are Few Plugins that will ease your work of Using Different Theme for Each Category in Wordpress.

Download the plugin here:

In case of GYS Themed Categories plugin:

Go to the required category :

Example:

http://yoursite.com/wp-admin/categories.php?action=edit&cat_ID=5

You will find a Combo list Box

Select the required Theme and Update the Category.

Done!