In the early morning I try to clean up all of my ruby gems and use rvm gemset to create for multiple projects that make me easily to see which gems are using in which projects and keep it organized.

So to remove all ruby gems I run this code below:

1

gem list | cut -d" " -f1 | xargs gem uninstall -aIx

For more information: http://geekystuff.net/2009/01/14/remove-all-ruby-gems/