scan authorized_keys and show fingerprints

gistfile1.rb

#!/usr/bin/env ruby
require 'tempfile'
IO.foreach(File.join(ENV['HOME'], '.ssh/authorized_keys')).each do |line|
  Tempfile.open("key") do |f|
    f.puts line
    f.flush
    r = `ssh-keygen -lf #{f.path}`
    r.sub!(f.path, '')
    puts r if $? == 0
  end
end