gistfile1.rb

#routes.rb
Rails.application.routes.draw do
  match '/blog'               => 'cms#blog'
  match '/blog/:id'           => 'cms#post'
  match '/categories/:id'     => 'cms#category'
  match '/tags/:id'           => 'cms#tag'
  match '/:id'                => 'cms#page'
end

#cms_controller.rb
class CmsController < ApplicationController
  def post
    @post = Post.find(params[:id])
    respond_to do |format|
      format.html # index.html.erb
    end 
  end 
  def page
    @page = Page.find(params[:id])
    respond_to do |format|
      format.html # index.html.erb
    end 
  end 
  def category
    @category = Category.find(params[:id])
    respond_to do |format|
      format.html # index.html.erb
    end 
  end 
  def tag 
    @tag = Tag.find(params[:id])
    respond_to do |format|
      format.html # index.html.erb
    end 
  end 
  def blog
    @posts = Post.all
    respond_to do |format|
      format.html # index.html.erb
    end 
  end 
end
~