What plugin\gem do you advice to use in order to add tag functionalities to my web application?

I am using Ruby on Rails 3.1 and I would like to add tag functionalities to my web application.

Do you advice to use a plugin\gem? If so, what plugin\gem do you advice to us开发者_JS百科e?

acts-as-taggable-on is an universal solution for tags implentation in Rails.

There are plenty. Checkout ruby-toolbox for options.