convert_currency.rb

#!/usr/bin/env ruby

require 'net/http'

def convert_currency(from_curr, to_curr)
  doc = Net::HTTP.get('www.google.com', "/finance/converter?a=1&from=#{from_curr}&to=#{to_curr}")
  regexp = Regexp.new("(\\d+\\.{0,1}\\d*)\\s+#{to_curr}")
  regexp.match doc
  $1.to_f
end

puts "1 USD = #{convert_currency('USD', 'EUR')} EUR"