Simple script uses fog to provision an EC2 instance

ec2_fog_server_provision.rb

#!/usr/bin/ruby
require 'rubygems'
require 'fog'

# Credentials in ./config.rb
require "./config.rb"

# Set up a connection
connection = Fog::Compute.new(:provider => 'AWS', :aws_access_key_id => @aws_access_key_id,
                                                  :aws_secret_access_key => @aws_secret_access_key)

server = connection.servers.create(:image_id => @ami_id,
                                   :flavor_id =>  @default_instance_type,
                                   :key_name => @key_name,
                                   :availability_zone => @availability_zone)

# wait for it to be ready to do stuff
server.wait_for { print "."; ready? }

puts "Public IP Address: #{server.public_ip_address}"
puts "Private IP Address: #{server.private_ip_address}"