XamimeLT is an email scanner which encapsulates your existing sendmail or Postfix server setup. It scans both incoming and outgoing email. It can scan for email viruses, unwanted file types (eg. EXE, BMP, MPEG) and file names (eg. prettypark.exe), spam, and almost anything you care to search for in an email. It can also be used to scan for text snippets within emails and to insert disclaimers into outbound emails. XamimeLT was formerly known as "Inflex".
ir is an interface program to Chris Dodge's RedRat 2 infrared controller to send and receive infrared signals to/from consumer devices like TV's, VCR's, cable boxes, and stereos. It will not work with any other IR tranceiver, like IrDA. It is written in Perl. It uses only the basic Perl constructs and no external packages, so it should work on any platform that supports Perl and serial communications. It can be accessed via the command line or cron, as an email handler (through aliases), or as a cgi script which will automatically generate a form with all possible codes. It has macro capability so one command can send a series of IR signals. With an X-10's IR543, it can be used to control X10 devices, too.
John the Ripper is a fast password cracker, currently available for many flavors of Unix, Windows, DOS, BeOS, and OpenVMS. Its primary purpose is to detect weak Unix passwords. It supports several crypt(3) password hash types commonly found on Unix systems, as well as Windows LM hashes. On top of this, lots of other hashes and ciphers are added in the community-enhanced version (-jumbo), and some are added in John the Ripper Pro.
logsurfer is a log checking/auditing tool similar to swatch and logcheck but with the capability of handling multi-line messages and dynamically adapting the ruleset. It is written in portable C, well documented, fast, and flexible. It works on any textfile or stdin, can be run at intervals or continuously, and has timeouts and resource limits.