Within the past 5 minutes I receive an email message and marked it as spam based on an RBL. This all done within the Erlang based SMTP server that I am writing.
Within the next few days I will be able to send the good message along to the final destination server and have the RBL processing involved. After that it is a process of creating more anti-spam processes and incorporating them into the SMTP server.
Privately I have been estimating that I will have a working beta on or before the 1st of the year. Looks like I might beat that goal by a week or two.
All of this would not have been possible without the power and flexibility of Erlang.