Perl is a high-level, general-purpose programming language that makes easy things easy and hard things possible. It is optimized for scanning arbitrary text files and system administration. It has built-in extended regular expression matching and replacement, a dataflow mechanism to improve security with setuid scripts and is extensible via modules that can interface to C libraries.
dvd::rip is a full featured DVD copy program written in Perl. It provides an easy-to-use but feature-rich GTK+ GUI to control almost all aspects of the ripping and transcoding process. It uses the widely known video processing swissknife, transcode, and many other Open Source tools.
The procmail and formail mail processing package can be used to create mail-servers, mailing lists, sort your incoming mail into separate folders/files (real convenient when subscribing to one or more mailing lists or for prioritising your mail), preprocess your mail, start any programs upon mail arrival (e.g. to generate different chimes on your workstation for different types of mail) or selectively forward certain incoming mail automatically to someone.
Ion is a tiling (no overlapping windows) window manager that also has PWM-style tabbed frames which can contain multiple client windows. These features help to keep windows organized and to switch quickly between them. Ion was designed primarily as an efficient and unobtrusive window manager for users who prefer the keyboard.
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.
GSview is a graphical interface for Ghostscript, an interpreter for the PostScript page description language used by laser printers. For documents following the Adobe PostScript Document Structuring Conventions, it allows selected pages to be viewed or printed. GSview requires Ghostscript 7 or later.