home_controller.rb

class HomeController < ApplicationController
  def index
    # render the landing page
    redirect_to root_url
  end

  def show
    if params[:page].nil? || params[:page] == :home
      render :action => :home
    else
      render :action => params[:page]
    end
  end
  
end

routes.rb

ActionController::Routing::Routes.draw do |map|
  # static pages
  map.home ':page', :controller => 'home', :action => 'show', :page => /about|terms|privacy|home/

  # default
  map.root :home
end