snippet.rb

# assumes you've got a copy of 'who let the dogs out' in your tmp dir
require 'rubygems'
require 'rest_client'

$url = "http://www.brownpapertickets.com/event/72123"

def site_up?
   RestClient::get($url) rescue false
end

def announce_site_is_up!
  puts ":)"
  `open /tmp/dogs.mp3`
end

def poll_site!
  loop do
    puts "checking..."
    announce_site_is_up! if site_up?
    sleep 60    
  end
end

poll_site!