Have you ever wanted your visitors to change how your site looks on the frontend? WP User Style Sheet Switcher is just the plugin for the job. It is a simple tool that lets you add stylesheet options in the backend with name, CSS file name, and other info. The default option can be rotated if you prefer.
You can have any number of stylesheet options. You can create multiple lists on each page and use this with a shortcode, widgets, or PHP functions. When an option is chosen on the frontend, the page is reloaded using the chosen stylesheet.
This plugin is available as a free download.