gistfile1.rb

class FailController < ApplicationController
  def index
    Fail.add_request(request.host, request.path, request.env['HTTP_REFERER'] || '', request.remote_ip || "0.0.0.0") 
    
    respond_to do |format| 
      format.html { render :file => "#{RAILS_ROOT}/public/404.html", :status => "404 Not Found" } 
      format.all { render :nothing => true, :status => "404 Not Found" } 
    end
    
  end
end

gistfile2.rb

class Fail < ActiveRecord::Base
  
  def self.add_request(host, path, referrer, ip)
    fail = find_or_initialize_by_host_and_path_and_referer(host, path, referrer) 
    fail.count = 1 + fail.count
    fail.save
    UserMailer.deliver_root("Got FAIL!", "Host #{host}, Path #{path}, Referer #{referrer}, IP #{ip}, count #{fail.count}")
  end
  
end