SAProxy

Free windows based pop3 proxy for SpamAssassin.

SAProxy is based on [http://mcd.perlmonk.org/pop3proxy/ Pop3Proxy] from Dan Mc Donald. It is an open source (perl) proxy server that seems to mostly work for Windows machines. Setting it up is *not* point-and-click easy, however.

SAProxy was derived/repackaged by Daniel Quinlan commisioned by [http://www.statalabs.com/ Stata Labs´s].

Notes:

• Free; With GUI
  
• SaProxyByHand: How to install SaProxy (without SpamAssassin) from scratch. Not for heart-fainted people, but works for latest SpamAssassin versions (that need to be installed apart)
  
• SpamAssassin Windows How To: How to install SpamAssassin in Windows
  

• Old version, easy to install, includes (old version) of SpamAssassin:
  There used to be a "handly available" free version. [http://www.statalabs.com/ Stata Lab´s FAQ] said (not anymore).
  What happened to the free version? - Last year, Stata Lab´s offered a free open source version of SAproxy 1.2. This version could also be found in the Open Source community for SpamAssassin. However, the product did not have a simple configuration or intuitive user interface, and, as a result, was difficult for the majority of users to understand and implement. In order to bring the power of SAproxy to a larger audience of users, Stata Labs put in a significant amount of effort to create, SAproxy Pro, which is easier to use, configure and refine. SAproxy Pro is the commercial version of SAproxy, complete with support and ongoing improvements.
  Currently (9 September 2004) Stata Lab´s web said: [http://www.statalabs.com/support/saproxypro/WebHelp/About_Spam_Assassin.htm]
  SAproxy Pro complies with the Perl Artistic License in the following ways:
  Following 3(a) by placing the modifications in the Public Domain
  Following 4(b) by distributing a standard version of SpamAssassin, which is available here [http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/spamassassin/] under the "spamassassin" module
  

Stata Labs' SAProxy PRO

Currently a non-free derived-version of SAProxy

• [http://www.statalabs.com/products/saproxy/overview.php SAProxy] by Bloomba is a Windows proxy server that's easy to set up and works quite well. It's $30.
  

Seem to be some claims regarding support.