Create callbacks to methods that you can easily and dynamically create/remove. Quite useful for lightweight event based programming. Even the medic agrees. If there's any kind of feature you think this gem is missing or if there is a bug, feel free to email me at firstname.lastname@example.org any time. Special thanks to: My brother Matt, m_x (http://codereview.stackexchange.com/users/24548/m-x), and Cary Swoveland (http://codereview.stackexchange.com/users/30157/cary-swoveland)'