bbkeys is the keygrabber for the Blackbox window manager. bbkeys handles all keybindings and keyboard shortcuts for Blackbox. It uses Blackbox's Image classes for rendering its look and feel, so bbkeys will draw itself to match whatever Blackbox style is used. It is highly configurable via the bbconf GUI utility, the included bbkeysconf.pl perl script, or via hand-editing bbkeys's config file.
beep does what you'd expect: it beeps. But unlike printf("\a"), beep allows you to control pitch, duration, and repetitions. Its job is to live inside shell/perl scripts and allow more granularity than one has otherwise. It is controlled completely through command line options. It's not supposed to be complex, and it isn't - but it makes system monitoring (or whatever else it gets hacked onto) that much more informative.
bfr maintains a buffer of data collected from stdin, emitting the data to stdout. It will both read and write at the speed each stream can handle, and allows you to set thresholds of when to start outputting and inputting again (after reaching a full buffer), the size of the buffer, as well as monitor content/throughput with an optional progress-bar. It also includes bfp, a variant especially written to play audio data using /dev/dsp.
BottleRocket is a utility to allow the use of the X10 FireCracker wireless appliance control kit under Linux, FreeBSD, NetBSD and more; porting to other systems usually just requires changing the serial port device. It covers all of the major non-GUI functions of the X10 software for windows, plus many other features.
Boxes is a text filter that can draw any kind of box around its input text. Box design choices range from simple boxes to complex ASCII art. A box can also be removed and repaired, even if it has been badly damaged by editing of the text inside. Since the generated boxes may be open on any side, the program can also be used to create regional comments in any programming language. New box designs of all sorts can easily be added and shared by appending to a free format configuration file. In addition to being a command line tool, Boxes integrates well with any text editor that supports filters.