pop_mailChecker.rb

require 'net/pop'

SERVER   = 'pop.example.com'
ACCOUNT  = 'example@example.com'
PADDWORD = 'password'
PORT     = 995


# use APOP authentication if $isapop == true
pop = Net::POP3.APOP($isapop).new(SERVER, PORT)
pop.enable_ssl # enable SSL if need.
pop.start ACCOUNT, PASSWORD

if pop.mails.empty?
  puts 'No mail.'
else
  puts "You have #{pop.mails.length} new messages."
end