Ember makes it easy to add an action to a button or an anchor tag with the {{action}} helper, but sometimes you need more control. Delegation works out really well. You create a view, specify the delegate, and the function(s) you want called. The nice thing is you can add as many actions as you want the view to have and you can reuse it for different controllers.

App.HoverView = Em.View.extend({
  tagName: 'span',
  mouseEnter: function(){
    this.get('delegate').send(this.get('action'));
  },
  mouseLeave: function(){
    this.get('delegate').send(this.get('action'));
  }
});

I've been using this pattern to give better control around TextFields and hovering actions such as the one above.