rails 3, how add a view that does not use same layout as rest of app?

By default, layouts/application.html.haml (.erb if you are not using haml).

In fact, layout file could be set per controller or per action, instead of per view, per view folder.

There are few cases:

To change the default layout file for all controller (ie. use another.html.haml instead of application.html.haml)

class ApplicationController < ActionController::Base
  layout "another"

  # another way
  layout :another_by_method
  private
  def another_by_method
    if current_user.nil?
      "normal_layout"
    else
      "member_layout"
    end
  end
end

To change all actions in a certain controller to use another layout file

class SessionsController < ActionController::Base
  layout "sessions_layout"
  # similar to the case in application controller, you could assign a method instead
end

To change an action to use other layout file

def my_action
  if current_user.nil?
    render :layout => "normal_layout"
  else
    render :action => "could_like_this", :layout => "member_layout"
  end
end