mconv is an Internet BBS modelled after Monochrome BBS (menus rather than a command line). It includes several utilities for the conversion of BBS attributes to plain text, ANSI colour text, and HTML. It can also convert session logs and scrollback buffers to BBS format so they can be viewed in the BBS or in the included standalone file viewer.
Simple Rescue CD is a small Linux rescue CD, suitable for booting systems that have become unbootable due to filesystem corruption or other problems. It lies somewhere between minimalist boot floppies and large full-featured rescue systems, and as such is suitable for when space is tight, such as on business card CDs.
pv (Pipe Viewer) is a terminal-based tool for monitoring the progress of data through a pipeline. It can be inserted into any normal pipeline between two processes to give a visual indication of how quickly data is passing through, how long it has taken, how near to completion it is, and an estimate of how long it will be until completion.
postprox is a minimal Postfix SMTP proxy which copies an SMTP conversation between its input and another SMTP server, but spools the DATA portion to a temporary file and runs a specified program on it before passing it on to the output server. It can potentially output an SMTP error code instead of the data if the content filter says to do so.
rt-emailimport is an extension that allows email to be imported from an IMAP mail server directly into Request Tracker, either to treat an email in your mailbox as if it had been sent to RT (complete with autoresponse) or to import one or more messages from a conversation directly into the history of an existing ticket.
rt-flagupdated is an extension that makes any tickets that are unread or have been updated get flagged in ticket listings. Unread tickets are marked with a "*" at the start of the subject line, and tickets with new comments since the last time they were read are marked with "UPDATED" at the start of the subject line.
Quick Spam Filter's accuracy
Just thought I'd point out that since this article was written, QSF (http://freshmeat.net/projects/qsf/) has got a lot more accurate - version 0.9.0 now comes in about third in the final test above, according to the article's author.