Attachment Ripper and Displacement System (aradis) is a filter that removes attachments from email. The removed attachment is sent to a specified resource for storage. The attachment is replaced with a notice of where the removed attachment may be found. The filter can also rename filenames for security. It uses GMime for MIME handling.
The Header and Envelope rewrite mini-HOWTO explains how to rewrite your from address differently in the mail header and the mail envelope. This may be necessary, for example, if your ISP requires you to send mail with one address, but you are subscribed to mailing lists with a different address, or want others to see a forwarding address instead of your ISP's address.
Spam Rule is a shell script that is designed to act as a filter for incoming mail on a qmail system. It runs between qmail-smtpd and qmail-queue, and can be used for any kind of filtering, although it was originally designed to block mail based on DNS blacklists (i.e. "RBLs"). Spam Rule is based upon the need to use different filtering rules based on who is receiving the message.
The Styler Ant Task makes useful combinations of XSLT and other transformations easy to specify in an Ant build file. Styler can handle multiple transformations, in parallel or pipelined, split or merge files, process non-XML files such as HTML (based on JTidy), apply non-XSLT transformation, such as "regular fragmentations" and use any custom XMLReader or XMLFilter class to handle new file formats and transformation techniques.
The SpamBouncer is a set of procmail instructions that search the headers and text of your incoming email to see if it meets one or more of a list of conditions for probable spam. It will then either tag the suspected spam and return it to your main incoming mailbox, tag the suspected spam, delete spam from known spam sources, and file suspected spam in a separate folder, send a simulated MAILER-DAEMON daemon "bounce", complain to the "upstream providers" of known spammers or spam sites/domains, etc.
info2man converts GNU info files to pod or -man formats. GNU info can be a pain as it demands its own special pager, it's a binary format, it's cruder than HTML and less documented, and most GNU- authored manual entries basically say "we like info so we don't maintain this manual entry, thus it is probably wrong". info2man thus converts info files so that they can be read by ordinary tools.