Balance is a simple but powerful generic TCP proxy with round-robin load balancing and failover mechanisms. Its behavior can be controlled at runtime using a simple command line syntax. Balance supports IPv6 on the listening side, which makes it a very useful tool for IPv6 migration of IPv4 only services and servers.
Beaver is an Early AdVanced EditoR, for Linux and other Unices (and even Windows); in other words, it's a text editor that is intended to be light-weight, but full of useful features for programming, from editing of web sites to C coding. It is based upon the GTK+ toolkit, supports many languages, and offers functions such as automatic indentation and syntax highlighting.
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.
BetaFTPD is a single-threaded FTP daemon. The single-threadedness makes it faster than most other FTP daemons (contrary to common belief), and makes it extremely light on memory. Although it lacks a few functions (which you probably won't miss), the current version is very small and has a decent amount of functionality. BetaFTPD is built on the concept of heavy code reuse, which should hopefully make it easier for other programmers to contribute.
BFBTester is good for doing quick, proactive security checks of binary programs. BFBTester will perform checks of single and multiple argument command line overflows and environment variable overflows. It can also watch for tempfile creation activity to alert the user of any programs using unsafe tempfile names.
Bicycle Ride Calorie Calculator is a simple program that calculates the number of calories expended on a bicycle ride. It is based on an article in the May 1989 issue of Bicycling Magazine, pp. 100-103. It provides a good estimate of the number of calories burned based on time, distance, rider weight, wind speed and direction, drafting, and climbing.