The 6.3.26 version of Fetchmail for Mac was available to download on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. The actual developer of this free software for Mac is Fetchmail Team. The application is included in Communication Tools.
From the developer:
Fetchmail is a full-featured, robust, well-documented remote-mail retrieval and forwarding utility intended to be used over on-demand TCP/IP links (such as SLIP or PPP connections). It supports every remote-mail protocol now in use on the Internet: POP2, POP3, RPOP, APOP, KPOP, all flavors of IMAP, ETRN, and ODMR. It can even support IPv6 and IPSEC.
You may want to check out more Mac applications, such as MailServe for Leopard or LaunchList, which might be similar to Fetchmail.