gistfile1.rb

#!/usr/bin/env ruby
require 'uri'

def isgd(url)
  `curl http://is.gd/api.php?longurl=#{URI.encode(url)}`
end

def pbcopy(string)
  `echo #{string} | pbcopy`
  return string
end

if ARGV[0]
  puts pbcopy(isgd(ARGV[0]))
else
  puts pbcopy(isgd(`pbpaste`.strip))
end