In my Rails application, I am looking to implement a tagging system for models. I want to create a tag selection feature similar to Stack Overflow where I can type in a tag like 'rails' and a drop-down list of options containing that tag will appear. From there, I can select and add more tags. Is there a plugin available that offers this functionality?
I am capable of setting up the tag model and migrations on my own, so that is not a concern for me. However, I need assistance with handling AJAX and javascript. My current setup involves prototype and Rails 2.3.