xmlsd is a library that wraps expat in order to simplify XML use in C programs as well as adding rigid rules to an XML structure. The idea is to have XML structures that can be passed over the network with implicit parameter verification. This in turn enables back and forth chattering between applications.
GNOME Clipboard Manager (GCM) makes copying and pasting easier and more productive. It will automatically synchronize the mouse selection (the primary selection) with the clipboard (the clipboard selection) and store the contents of the clipboard, making it possible to go back to a previous clipboard. You can save and load clipboards, edit them, and convert them to another format.
Ficl (Forth inspired command language) is an ANS Forth interpreter written in C. Unlike traditional Forths, this interpreter is designed to be embedded into other systems as a command/macro/development prototype language. Ficl provides object extensions that can be used to wrap methods and structures of the host system without altering them.
mod_backhand is a load balancing module for Apache. It provides per-request HTTP redirection within a heterogeneous Apache server cluster. Each request is processed and run through a set of "candidacy functions" to determine which server is best suited to respond. The request is then proxied to that server. Facilities are in place to allow you to write your own dynamically loadable decision making algorithms. Everything about the request and the current availability of resources can be used in the decision-making process.
Libbt is a C-language implementation of the BitTorrent protocol suite for Unix that was designed to be linked into a variety of languages. It is implemented as a memory-efficient single threaded library, and has fdset maintenance that can be used to either add in to your select loop or its own main loop.
dwarf-ng is a small and powerful object file manipulator. With dwarf-ng, you can read, edit, and manipulate section headers, inject code or data, and create new section headers of object files. Currently, it handles object files in the PE, Mach-O, and ELF formats. For the moment, dwarf-ng only has a command-line interface. dwarf-ng is fully scriptable (as it has a scripting language), and is flexibly configurable.